Tea has a vocabulary problem. Half the words on a tin sound like marketing, some are translations that stuck, and the rest are precise terms that get used rather loosely. Three worth sorting out immediately: fermentation, which often means oxidation in older tea terminology; tannins, which people use as shorthand for a drying sensation; and orange pekoe, which is a leaf grade, not an orange-flavored tea.
The terms below are grouped by what they describe, because most of them make more sense next to their neighbors. If you're looking for one word, use your browser's Find function. There's no prize for reading a glossary from beginning to end.
How tea is made.
Every true tea comes from the same plant species. What separates the different kinds is what happens to the leaf between the field and the tin, and most of these words name one part of that process.
Camellia sinensis
The tea plant. Green, white, yellow, oolong, black and dark teas, including pu-erh, all come from this species.
Two botanical varieties you'll often encounter are Camellia sinensis var. sinensis, generally associated with smaller leaves and better cold tolerance, and var. assamica, commonly associated with larger leaves and warmer growing regions. Chinese and Japanese tea production uses many small-leaf cultivars, while large-leaf plants are important in Assam and Yunnan. Actual tea gardens contain more diversity than those two labels suggest.
Herbal tea (tisane)
Not tea in the botanical sense. Chamomile, peppermint, rooibos and hibiscus contain no leaf from Camellia sinensis. The more precise word is tisane, though nobody needs to correct someone for ordering peppermint tea.
Herbal infusions have their own brewing requirements, and many common ones are naturally caffeine-free. Not all are. Yerba mate and guayusa are botanical infusions that contain caffeine, so the word herbal isn't a promise about what will keep you awake.
Withering
Usually one of the first steps after harvest. Fresh leaves lose some moisture, becoming softer and easier to handle while chemical changes begin developing aroma.
Time, airflow, temperature and humidity all matter. It may look like waiting around, but a poorly controlled wither can affect the finished tea. Japanese steamed green teas are an important exception to the usual sequence: they're generally heated soon after harvest, with little or no deliberate withering beforehand.
Oxidation
One of the most important words in tea production, and the one frequently called fermentation in older tea terminology.
When leaf cells are disrupted, naturally occurring enzymes and compounds can react with oxygen. That changes the leaf's color and chemistry, somewhat like the browning of a cut apple.
Green tea is heated early to limit these reactions. Oolong undergoes partial oxidation. Black tea undergoes extensive oxidation. White tea follows a different, gentler processing route in which some oxidation can occur during withering and drying.
Oxidation matters enormously, but it's not the only thing that determines a tea's flavor. Our guide to green, black, oolong and white tea explains how the different processing choices shape the cup.
Fixing (kill-green)
Heating the leaf to deactivate the enzymes responsible for much of its oxidation. In Chinese tea making, the process is called sha qing, usually translated as kill-green.
Many Chinese green teas are pan-fired, which can contribute toasted or nutty aromas. Most Japanese green teas are steamed, often producing a more vegetal or marine character.
Fixing stops the main enzymatic oxidation process. It doesn't mean the leaf can never undergo another chemical change during drying or storage. Tea would be considerably easier to explain if it worked that way.
Rolling
Shaping the leaves by twisting, pressing or rolling them. Depending on the tea, it can also disrupt cells and encourage the reactions that develop flavor.
Rolling produces the needles, twists and tightly curled pellets different teas are known for. Some oolongs unfold gradually over several infusions, which is part of the pleasure of brewing them more than once.
Not every tea is rolled. Traditional tencha, for example, is dried without rolling before being ground into matcha.
Firing (drying)
Applying heat to reduce the leaf's moisture so it can be stored without spoiling. Different methods and temperatures influence the finished aroma and flavor.
In some tea-making traditions, firing also refers to deliberate roasting. With oolong, an additional roast can transform a floral tea into something deeper, nuttier and more toasted.
Drying and roasting are related, but they aren't necessarily the same job.
Fermentation
A word with two meanings in the tea world, which explains a remarkable amount of confusion.
In older industry terminology, black tea may be called fully fermented and oolong semi-fermented. In those cases, the process being described is primarily enzymatic oxidation, not fermentation by microorganisms.
In dark teas such as ripe pu-erh, microorganisms are involved in transforming the leaf. This is microbial fermentation, also called post-fermentation. Raw pu-erh can also undergo gradual chemical and microbial changes during storage, though its aging process differs from the controlled wet-piling used for ripe pu-erh.
If a black tea tin says fully fermented, it usually means extensively oxidized. If a ripe pu-erh seller says fermented, they're talking about a different process. Same word, different work.
Shading
Reducing sunlight before harvest by covering tea plants with screens, cloth or other shade structures.
Kabusecha is generally shaded for roughly one to two weeks. Gyokuro and tea intended for traditional matcha production are commonly shaded for around three weeks or longer, although growing methods vary.
Shading changes the plant's metabolism. It can increase chlorophyll and alter the balance of amino acids, caffeine and catechins, helping produce the deep green color and savory character associated with gyokuro and matcha.
The short explanation is that shade encourages a different chemical balance. The longer explanation involves how the plant makes, transports and uses those compounds. The leaf doesn't simply turn all its sweetness into bitterness when the sun comes out.
Flush
A period of new growth and the harvest associated with it.
Darjeeling is especially known for its first flush, harvested in spring, and second flush, generally harvested in late spring and early summer. First-flush teas are often lighter and more floral. Second-flush teas can be fuller, with the distinctive grape-like character described as muscatel.
Both come from tea gardens in the same region, sometimes from the same bushes, but changing seasons produce noticeably different leaves.
Shincha
Japanese for new tea. Usually the first flush of Japanese green tea sold soon after the spring harvest.
Its appeal is freshness: bright aroma, lively flavor and the feeling that the leaves haven't spent very long waiting for you. Drink it relatively soon for that character, and store it carefully. It doesn't become undrinkable after a few weeks.
The six types.
Traditional Chinese tea classification recognizes six main categories based largely on processing. In English-language introductions, you'll usually meet four: green, white, oolong and black. Yellow and dark tea complete the family.
Green tea
Tea heated early to limit enzymatic oxidation. It can taste grassy, vegetal, nutty, sweet or savory, depending on the leaf and whether it was steamed, pan-fired or processed another way.
Delicate green teas often become harsh when brewed with water that's too hot, which explains a good portion of their reputation for bitterness.
White tea
Usually withered and dried with relatively little handling, generally without deliberate rolling or an early fixing step.
White tea can be delicate, floral and sweet, but the category also includes fuller, fruitier teas and styles intended for aging. It's often sold as naturally low in caffeine. That isn't a dependable rule.
Yellow tea
A relatively uncommon Chinese tea made using a process related to green tea production, with an additional controlled yellowing stage often called men huang.
The leaves are held under warm, moist conditions for a period, changing their color and softening some of the sharper green characteristics. The result is often smoother and rounder than a comparable green tea.
Not the easiest category to find outside China, but worth remembering when you come across one.
Oolong
Partially oxidized tea that can range from light and floral to dark, roasted and richly aromatic.
You'll see figures such as 10–80% oxidation used to describe that range. Treat those numbers cautiously. There isn't a universally applied measurement behind every percentage printed on a tea listing.
A lightly oxidized oolong can resemble green tea. A heavily roasted one may taste closer to black tea, although roasting and oxidation are two different things.
The most rewarding category to explore, and possibly the hardest to summarize in one sentence.
Black tea
Tea that undergoes extensive enzymatic oxidation during processing. Called hong cha, or red tea, in Chinese, after the reddish color of the infusion.
Black teas can be malty, brisk, floral, fruity or sweet. Strong breakfast blends handle hot water and milk well, while delicate black teas such as some Darjeelings deserve a gentler approach.
The category is generally forgiving. Not every individual tea within it is.
Dark tea (hei cha)
A category of Chinese post-fermented teas in which microorganisms contribute to changes in the leaves during processing or aging.
Dark teas may be sold loose or compressed into bricks, cakes and other shapes. They include styles such as Fu brick tea, Liu Bao and ripe pu-erh.
The name creates confusion because hei cha translates literally as black or dark tea. English uses dark tea to distinguish this group from the extensively oxidized teas called black tea in the West.
Pu-erh
Tea associated with Yunnan, China, and commonly made from large-leaf tea plants. It may be sold loose or pressed into cakes, bricks and other shapes.
Two major styles dominate: sheng, or raw pu-erh, and shou, or ripe pu-erh. Their production and aging are different enough that knowing which one you're buying matters more than recognizing the word pu-erh.
Raw pu-erh's classification alongside dark tea can vary with processing, age and the classification system being used. Ripe pu-erh is a clearer example of deliberately microbially fermented tea.
Sheng (raw) pu-erh
Pu-erh made without the accelerated wet-piling process used for ripe tea.
Young sheng can be bright, grassy, bitter or astringent. During storage it can change gradually through oxidation and microbial activity, developing deeper and softer characteristics.
Good aging depends on the tea and its storage conditions. Time alone doesn't turn every rough young cake into treasure. It has to be good tea before the calendar gets involved.
Shou (ripe) pu-erh
Pu-erh made using controlled wet-piling, called wo dui, which encourages microbial fermentation under warm, moist conditions.
The modern process was developed in Yunnan during the early 1970s to produce some of the darker characteristics associated with aged raw tea in a much shorter time.
Ripe pu-erh is often smooth, earthy, dark and full-bodied. It's meant to be enjoyed as its own style, not merely as a substitute for old sheng.
Japanese teas.
Sencha
Japan's familiar everyday loose-leaf green tea. Usually steamed, rolled and dried into slender, needle-like leaves.
Sencha can be grassy, vegetal, savory or pleasantly astringent. The exact character depends on the cultivar, growing conditions and processing.
Fukamushi means deep-steamed. These teas are steamed longer than ordinary sencha, often leaving more fragmented leaves and producing a cloudier, more intensely colored infusion with a softer mouthfeel.
Gyokuro
A Japanese green tea made from leaves shaded for several weeks before harvest.
Deeply savory, rich in aroma and prized for its concentrated umami character. It's often brewed with relatively cool water, sometimes around 120–150°F, using a higher leaf-to-water ratio than ordinary sencha.
Specific brewing instructions vary, but pouring boiling water directly onto an expensive gyokuro is generally a poor first experiment.
Kabusecha
A Japanese green tea made from leaves shaded for a shorter period than traditional gyokuro, commonly around one to two weeks.
It often sits between unshaded sencha and gyokuro in flavor, balancing fresh green notes with a sweeter, more savory character. The name describes how the tea was grown, not a precise flavor or price.
Matcha
Finely powdered Japanese green tea, traditionally made from shaded tencha.
The plants are shaded before harvest. The leaves are steamed and dried without rolling, then the stems and major veins are removed before grinding. Stone mills are traditional, though modern milling equipment is also used.
Instead of steeping the leaves and removing them, you whisk the powder into water and drink the suspended leaf itself. That gives matcha its concentrated character and changes how much caffeine and other leaf compounds end up in a serving.
You'll often see matcha sold as ceremonial grade. That describes a seller's intended quality or use, not an official Japanese grading standard. A better buying guide is the producer, origin, freshness, flavor and intended use.
For a more detailed explanation of the traditional production method, see Japan's trade organization JETRO's guide to matcha.
Tencha
The processed, unground tea leaf used to make traditional matcha.
It's grown under shade, steamed and dried without rolling before the stems and major veins are separated. Tencha can also be brewed as a loose-leaf tea, though most people encounter it after it's been ground.
Bancha
A broad term for everyday Japanese tea, often made from later harvests or more mature leaves.
Bancha is frequently less expensive than sencha and can have a mild, rustic character. It's sometimes lower in caffeine, depending on the leaf material and brewing method, but the name alone doesn't guarantee that.
Hojicha
Japanese roasted green tea, often made from bancha, sencha or stems.
Roasting turns the leaf brown and produces toasted, nutty aromas with less of the grassy character associated with fresh green tea.
Hojicha is often sold as a lower-caffeine choice, especially when made from mature leaves or stems. Its caffeine content still varies. Roasting doesn't automatically remove all the caffeine, however reassuring the aroma may be.
Genmaicha
Japanese green tea mixed with roasted rice. Some rice grains puff during roasting, giving the blend its familiar popcorn-like appearance.
The result is nutty, toasted and savory. The rice also means there's less tea leaf in a given weight of blend, although the caffeine in the finished cup still depends on how much you use.
Kukicha
Tea made primarily from stems, stalks or twigs of the tea plant, rather than the usual leaf material.
Japanese kukicha is often associated with green tea production and can taste sweet, mild or lightly savory. Stems frequently contain less caffeine than young leaf buds, but the exact amount depends on the material and preparation.
Better than the phrase made from twigs has any right to suggest.
Kyusu
A Japanese teapot. The most recognizable type has a side handle and a built-in strainer, making it convenient for short steeps and quick, complete pours.
Not all kyusu are side-handled, but that's the style most people picture.
Chinese, Indian and Sri Lankan teas worth knowing.
Longjing (Dragon Well)
One of China's best-known green teas, traditionally associated with the area around Hangzhou in Zhejiang.
Its flat leaves are shaped during pan-firing. Good examples can be sweet, smooth and nutty, sometimes with a chestnut-like aroma.
Tieguanyin (Iron Goddess)
A famous oolong associated with Anxi in Fujian, China.
Often rolled into tight pellets and produced in styles ranging from light, green and floral to darker, more roasted versions. The name doesn't tell you how heavily roasted the tea will be.
Da Hong Pao
One of the most famous names in Wuyi rock tea, or yancha, from Fujian.
The name means Big Red Robe. Da Hong Pao is associated with mineral, roasted and complex flavors, sometimes with fruit or floral notes.
The famous original mother bushes are not the source of ordinary retail tins. Modern Da Hong Pao is produced from cultivated material and may be sold as a blend.
Keemun
A black tea from Qimen County in Anhui, China.
Often aromatic and smooth, with notes that can suggest cocoa, dried fruit, flowers or a faint smokiness. Keemun has also been used in English Breakfast blends, though not every breakfast blend contains it.
Assam
Tea from the Assam region of northeastern India, especially known for its robust black teas.
Often malty, strong and full-bodied, making it useful in breakfast blends and masala chai. The region is closely associated with large-leaf assamica tea plants.
Darjeeling
Tea from the Darjeeling growing region of West Bengal, India.
Often lighter and more floral than Assam, with differences between harvests. First-flush teas can be fresh and delicate; second-flush teas may develop the grape-like character called muscatel.
You'll hear it called the champagne of teas. There's a certain confidence in that comparison, especially when it comes from someone selling Darjeeling.
Ceylon
The traditional tea-trade name for tea from Sri Lanka.
Best known for black tea, though the country produces other types. Depending on the growing region and elevation, Ceylon teas can be brisk, citrusy, floral or full-bodied.
Some make excellent iced tea, but Ceylon is an origin, not one single flavor.
Silver Needle (Bai Hao Yin Zhen)
A white tea made from unopened tea buds, traditionally associated with Fujian, China.
Usually delicate, fragrant and comparatively expensive, with subtle sweet or floral notes.
Because young buds can contain substantial caffeine, Silver Needle isn't automatically low-caffeine. How much reaches your cup depends on the leaf quantity and brewing method.
Grades and cuts.
Whole leaf
Tea made from intact or relatively intact leaves.
Larger leaves often extract more slowly than finely broken tea and can be well suited to multiple infusions. Whole leaf isn't an automatic guarantee of quality, though. A well-made broken-leaf tea can be excellent.
Broken leaf
Tea with leaves broken into smaller pieces, either during processing or as a designated grade.
Smaller pieces expose more surface area and generally brew faster than large intact leaves under similar conditions. That can produce a strong, brisk cup, especially in black tea.
Fannings and dust
Small tea particle grades, with dust generally finer than fannings.
They're commonly used in standard tea bags because they extract quickly and consistently. Fine particles can become overly strong or bitter with a long steep, but they're not automatically defective or leftover rubbish.
The grade describes particle size, not whether somebody cared about the tea.
CTC (crush, tear, curl)
A mechanical tea-processing method that breaks leaves into relatively small, uniform particles or pellets.
It's widely used for strong black tea blends, including many breakfast teas and teas intended for milk or masala chai.
CTC is efficient and consistent. It doesn't settle the question of quality in either direction.
Orange pekoe
A grading term used mainly for black teas from regions such as India and Sri Lanka. It describes the physical form and appearance of the processed leaf.
Despite the name, it has nothing to do with oranges or orange flavor. The word pekoe belongs to a historical tea-grading vocabulary, not a flavor description.
Longer grade abbreviations, such as TGFOP or FTGFOP, add descriptions of leaf and tip appearance. They can indicate how a tea was sorted, but they don't guarantee that you'll enjoy drinking it.
Words on the label.
Liquor
The brewed liquid in your cup, as distinct from the dry leaf or the wet leaves after brewing.
Professional tea descriptions often discuss the liquor's color, clarity, aroma and taste. Nothing alcoholic is implied.
Brisk
A lively, bright quality, often accompanied by some astringency, especially in black tea.
Usually a compliment. Brisk tea has a little energy to its taste. Bitter tea simply wants your attention for the wrong reason.
Body
The weight, fullness and texture a tea seems to have in your mouth.
A tea may feel light and thin, full and rounded, or almost creamy. Strong Assam blends often have substantial body; delicate white teas can feel much lighter. Both can be excellent.
Malty
A flavor or aroma reminiscent of malt, warm grain, malted milk or fresh bread.
Especially common in descriptions of Assam black tea.
Tippy (golden tips)
Tea containing a noticeable proportion of young buds or tips.
In some black teas, these tips become golden during processing, which is why the word appears in grade abbreviations such as TGFOP.
Tips can influence the flavor and appearance of a tea, but more golden tips don't automatically mean sweeter, smoother or better. Their presence is one piece of information, not a verdict.
Single estate
Tea identified as coming from one tea estate or garden rather than being blended from multiple estates.
It tells you about origin, not necessarily about harvest date. A single-estate tea may come from one picking, several pickings or a producer's own blend. If you want one particular harvest, look for that information separately.
Blend
A combination of teas chosen to create a particular flavor, aroma or level of consistency.
English Breakfast is a familiar example. Blending can keep a brand's tea tasting similar from one season to the next, or create something that no individual component would produce alone.
It's a technique, not an admission of low quality.
Scented and flavored
Scented teas traditionally gain aroma through contact with fragrant ingredients, such as fresh jasmine blossoms placed near or among tea leaves during production.
Flavored teas have flavoring ingredients or extracts added. Earl Grey, usually flavored with bergamot, is the familiar example.
These methods can overlap in commercial products. A jasmine tea may be traditionally scented, flavored with added jasmine aroma, or made using a combination. The ingredient list is more useful than romantic descriptions of flowers in moonlight.
Organic, and the words that aren't regulated
Organic has a specific regulatory meaning in the United States. Products marketed as organic generally must follow USDA organic production and handling rules, with certification requirements and limited exemptions.
Products labeled organic normally need at least 95% certified organic ingredients, excluding salt and water. The separate made with organic category generally requires at least 70% organic ingredients and cannot display the USDA Organic seal.
You can check the distinctions in the USDA's organic labeling guidance.
Words such as premium, artisan, handcrafted and ceremonial do not establish a comparable universal tea-quality grade. They may describe something real, but the seller needs to tell you what.
A specific origin, harvest date, processing method or certification gives you something you can actually check. An adjective mostly gives you an adjective.
Brewing.
Infusion
The liquid produced when tea leaves are steeped in water. The word can also refer to a particular round of brewing.
Good tea may produce several worthwhile infusions, though the number depends on the tea, amount of leaf, water temperature and brewing method.
Leaf-to-water ratio
The amount of dry tea used relative to the amount of brewing water.
For ordinary mug or pot brewing, a useful starting point is 2–3 grams per 8 ounces of water. Some teas and brewing styles use considerably more.
Weigh the leaf at least once. A spoonful of fluffy white tea and a spoonful of rolled oolong can contain very different amounts. Spoons measure volume. Tea is inconveniently three-dimensional.
Western brewing
A loose term for brewing tea with a relatively small amount of leaf in a larger volume of water, usually in a mug or teapot.
A common approach is one infusion lasting roughly one to five minutes, depending on the tea. The method is convenient and familiar, though many leaves can be steeped again.
Gongfu cha
A Chinese approach to brewing tea using a relatively high leaf-to-water ratio and a series of shorter infusions.
A common starting range is roughly 1 gram of tea per 15–25 milliliters of water, adjusted for the tea, vessel and drinker's preference. Early steeps may last only a few seconds, gradually lengthening as the leaves give up more flavor.
The idea is to experience how a tea changes from one infusion to the next rather than taking everything from it in one long steep.
It asks for a little more attention. Whether that makes the tea better is up to the person holding the cup.
Gaiwan
A Chinese lidded bowl used for brewing tea, especially in gongfu-style sessions.
The lid holds back the leaves while the tea is poured. Porcelain gaiwans are inexpensive, easy to clean and useful for tasting many different teas without the vessel contributing much flavor of its own.
One of the most versatile pieces of tea equipment you can own, once you've learned how not to pour hot water onto your fingers.
Yixing pot
An unglazed clay teapot associated with Yixing in Jiangsu province, China, especially the region's traditional zisha stoneware.
These pots are often used for oolong, black tea and pu-erh. Their clay, wall thickness and heat retention can influence brewing, and the unglazed surface may interact with tea compounds over time.
You'll hear that an old Yixing pot remembers the flavor of every tea made in it. There's a practical tradition behind dedicating a pot to similar teas, but claims about dramatic flavor improvement through seasoning are difficult to establish.
Buy one because you enjoy the vessel and the way it brews, not because somebody promises the clay will eventually do the tasting for you.
Rinse
A very short preliminary infusion, usually poured away before the main brewing begins.
Common in some gongfu sessions, especially with compressed or aged teas. A rinse can wet and loosen tightly packed leaves and remove loose surface particles.
It's not universally necessary. Most loose green teas don't need one, and a quick rinse doesn't reliably decaffeinate tea. Caffeine extraction continues through later infusions.
Re-steeping
Brewing the same leaves more than once.
Many whole-leaf teas, particularly oolongs and pu-erh, can produce several interesting rounds. The flavors often change as the leaves unfold and different compounds continue to extract.
Tea bags made from fine particles generally have less to offer on a second steep, especially after a long first brew. But the result depends on how much was extracted the first time.
Agitation
Moving the leaves or water during brewing by stirring, swirling, dunking or otherwise disturbing the infusion.
Agitation can change the speed and uniformity of extraction. It doesn't selectively release only bitter compounds, and gently squeezing a tea bag doesn't unleash a hidden supply of tannins.
If your tea tastes harsh, check temperature, steeping time and leaf quantity before blaming the spoon.
Cold brew
Tea steeped in cold water, usually in the refrigerator for several hours. Six to twelve hours is a useful starting range, depending on the tea and how much leaf you use.
Cold water extracts compounds more slowly than hot water and can produce a smoother, less astringent flavor. The balance depends on the tea, temperature and steeping time.
Cold brewed doesn't mean caffeine-free. Caffeine still dissolves in cold water, and longer steeping can extract a meaningful amount. A cold brew may contain less caffeine than a comparable hot brew under some conditions, but that isn't a dependable rule for every recipe.
For food safety, use clean equipment and potable water, brew in the refrigerator, and keep the finished tea refrigerated.
Grandpa style
Tea brewed with loose leaves directly in a glass or mug, without a strainer. As you drink, you refill the vessel with hot water.
Common in parts of China, and particularly convenient with leaves that settle to the bottom and don't become aggressively bitter.
It's less ceremonial than gongfu brewing and more forgiving of an interrupted afternoon. The tea stays where it is; you come and go.
Taste and chemistry.
Astringency
A dry, puckering or rough feeling in the mouth rather than a basic taste like sweetness or bitterness.
Tea polyphenols can interact with proteins in saliva, changing the lubrication in your mouth and producing that familiar drying sensation.
Bitterness and astringency often occur together, but they aren't the same thing. A tea can be astringent without being especially bitter.
Cooler brewing water or a shorter steep may reduce both, depending on the tea. Our guide to bitter tea explains the practical fixes.
Bitterness
A basic taste produced when certain compounds activate bitter taste receptors.
In tea, caffeine and some catechins contribute to bitterness. The amount you perceive depends on the leaf, how it's processed and how you brew it.
A little bitterness can give tea structure. Too much overwhelms the more delicate flavors. Not every bitter cup was brewed incorrectly, but temperature and steeping time are sensible places to begin troubleshooting.
Umami
The savory, brothy taste associated with compounds such as glutamate.
It's especially noticeable in certain shaded Japanese green teas, including gyokuro and matcha. L-theanine and other tea compounds can enhance the perception of umami, but it's too simple to say that theanine alone creates that savory taste.
If a tea reminds you of broth rather than flowers or fruit, umami may be part of what you're noticing.
Polyphenols
A broad family of plant compounds that contribute to tea's flavor, color and astringency.
Catechins are important polyphenols in green tea. During black tea processing, many are transformed into other compounds, including theaflavins and thearubigins.
Polyphenol is a chemical category, not a synonym for bitterness or a guarantee of a particular health benefit.
Catechins
A group of polyphenols found in tea, especially important in green and white teas.
One of the best known is EGCG, short for epigallocatechin gallate. Along with other catechins, it contributes to green tea's bitter and astringent character.
During black tea production, many catechins are transformed into more complex oxidation products. That helps explain why green and black teas taste so different despite coming from the same plant.
Theaflavins and thearubigins
Groups of compounds formed during the extensive oxidation involved in making black tea.
They develop through reactions involving catechins and other leaf compounds, contributing to black tea's reddish color, body and briskness.
They're part of the chemistry behind black tea's distinctive character, not simply the bitter compounds from green tea given new names.
L-theanine
An amino acid strongly associated with tea, often discussed alongside caffeine.
It can contribute to tea's flavor and enhance savory taste in combination with other compounds. Its concentration varies with the plant, growing conditions and processing; shading can influence how the plant produces and distributes it.
L-theanine also appears frequently in claims about calm focus. Research has examined those effects, sometimes using isolated supplements or controlled combinations with caffeine. Results shouldn't be treated as promises about what any ordinary cup of tea will do.
It's a useful compound to know about. It doesn't need a personality or a superpower.
Tannins
A term often used loosely in tea writing to describe compounds associated with astringency.
In chemistry, tannins refer to groups of polyphenols capable of interacting with proteins. Some tea catechins, particularly gallated catechins, have tannin-like properties, and tea polyphenols are sometimes called tea tannins.
That doesn't make tannin a precise name for every bitter or drying substance in the cup. Caffeine contributes bitterness, for example, but isn't a tannin. Tannic acid is a specific chemical substance, not a useful general label for all of tea's polyphenols.
When somebody calls a tea tannic, they usually mean it feels astringent. That's a perfectly understandable tasting description, even if it doesn't tell you exactly which molecules are responsible.
Caffeine
A naturally occurring stimulant found in tea leaves.
Its concentration depends on factors such as plant genetics, leaf age and growing conditions. The amount in the finished cup also depends on how much tea you use, how finely it's cut, the water temperature and steeping time.
Tea color doesn't give you a reliable caffeine ranking. White tea isn't necessarily the lowest, and some bud-heavy white teas can contain substantial caffeine. Shade-grown teas may also have high caffeine levels, while matcha includes the powdered leaf itself rather than just an infusion.
Brewing with cooler water or for less time may reduce caffeine extraction, but it doesn't turn regular tea into decaf. Neither does rinsing the leaves for thirty seconds.
If caffeine is a major concern, look for a clearly labeled decaffeinated tea or a naturally caffeine-free infusion. Remember that decaf can still contain small amounts.
None of this vocabulary is needed to make a good cup. But knowing what a word actually means is usually the fastest way to work out whether the person using it does.