Coffee glossary
127 terms, plainly defined. Tap any word, or just .
A
- Acidity The bright, lively, sometimes fruity sharpness of a coffee; a positive quality when it is clean and pleasant.
- Affogato A shot of hot espresso poured over a scoop of vanilla ice cream or gelato; part drink, part dessert.
- Aftertaste The flavor and sensation that linger after you swallow coffee; the finish that can be clean, sweet, or harsh.
- Agitation Stirring, swirling, or pour force that speeds extraction and evens it out; a lever many recipes use.
- Alkalinity (KH/buffer) Water's buffering capacity, mostly bicarbonate, which tames acidity; too much flattens the cup.
- Altitude Growing elevation; higher and cooler usually means denser, sweeter, more acidic beans.
- Americano Espresso lengthened with hot water for a longer, lighter black coffee.
- Anaerobic fermentation Fermenting cherries or beans in sealed, oxygen-limited tanks to build intense, funky, distinctive flavors.
- Arabica The flavor-forward coffee species: sweeter and more complex, grown at altitude, around 60 to 70% of world production.
- Astringency A dry, puckering, sometimes harsh sensation in coffee, often a sign of over-extraction.
B
- Balance How well a coffee's acidity, sweetness, body, and bitterness fit together without any one dominating.
- Basket The perforated metal cup inside the portafilter that holds the dose; sized single, double, or VST.
- Bean density How hard and dense a green bean is; denser, higher-grown beans tend to be sweeter and more complex.
- Blade grinder A cheap grinder that chops beans with a spinning blade, producing very uneven dust and chunks; best avoided for coffee.
- Bloom The 30 to 45 second rest after first wetting grounds, letting CO2 escape so water extracts evenly.
- Body The weight and texture of coffee in your mouth, running from light and tea-like to round and syrupy.
- Boulders Oversized particles from uneven grinding that under-extract and dilute the cup.
- Bourbon A foundational arabica variety known for sweetness and balance, and the parent of many widely grown cultivars.
- Brew ratio The proportion of coffee to water, written like 1:16 for filter or 1:2 for espresso.
- Brightness A pleasant, vivid acidity that makes a cup feel lively, clear, and refreshing.
- Burr grinder A grinder that crushes beans between two abrasive burrs set a fixed distance apart, giving a uniform, adjustable grind.
- Bypass Water that slips past the grounds without extracting, then dilutes the finished brew.
C
- Caffeine The natural stimulant in coffee; arabica holds roughly 1.2 to 1.5% and robusta about 2.2 to 2.7% by bean weight.
- Cappuccino Espresso with roughly equal parts steamed milk and airy foam.
- Caramelization The browning of sugars under roasting heat that builds sweetness, color, and bittersweet depth in the cup.
- Carbonic maceration A wine-borrowed method fermenting whole cherries under CO2 for bold, fruit-forward, distinctive cups.
- Catuai A hardy, productive Mundo Novo x Caturra hybrid common in Brazil and Central America, in red and yellow forms.
- Caturra A compact, high-yielding natural mutation of Bourbon, widely grown across Latin America.
- Channeling Water punching a fast path through the coffee bed, causing uneven, sour-and-bitter extraction at once.
- Chemex An hourglass pour-over brewer using thick paper filters for a very clean, bright, light-bodied cup.
- Chlorogenic acid A family of antioxidant acids in green coffee that break down during roasting and shape acidity and bitterness.
- Clean cup A cup free of off-flavors and defects, where the intended flavors read clearly and distinctly.
- CO2 (in coffee) Carbon dioxide trapped during roasting that drives the bloom and crema, then fades as coffee degasses.
- Coffee cherry The fruit of the coffee plant; usually holding two seeds, the beans we eventually roast.
- Cold brew Coffee steeped in cold or room-temperature water for many hours, yielding a smooth, low-acid concentrate.
- Conical burr A burr set with a cone-shaped center spinning inside a ringed outer burr; efficient, cooler-running, common at home.
- Cortado Espresso cut with a small, equal amount of warm steamed milk, served in a small glass.
- Crema The reddish-brown foam on top of an espresso shot, made of emulsified oils and CO2.
- Cultivar A cultivated variety selected by humans; in coffee, used more or less interchangeably with varietal.
- Cupping The standardized tasting method used to evaluate and compare coffees on a level playing field.
D
- Dark roast A roast taken into or past second crack: bittersweet, smoky, oily-surfaced, with muted origin character.
- Decaffeinated coffee Coffee with most of its caffeine removed (typically 97% or more); reduced, not entirely caffeine-free.
- Defect A flawed bean (quaker, sour, insect-damaged, and more) that downgrades a lot and can taint the cup.
- Degassing Roasted coffee slowly releasing CO2 over days and weeks; why very fresh coffee can brew unevenly.
- Development time (DTR) The stretch of a roast from first crack to the end, often given as a percentage of total roast time; shapes sweetness and body.
- Direct trade Roasters buying straight from producers, aiming for traceability and better farmer prices.
- Doppio A double espresso pulled from a double basket, the modern default shot.
- Dose The mass of dry ground coffee used for a shot or brew, measured in grams.
- Drawdown The phase where water finishes draining through the bed in pour-over; its timing signals grind and flow.
- Drip / batch brew Automatic gravity brewing of coffee through a paper or metal filter; the everyday machine method.
E
- EA / sugarcane decaf Decaffeination with ethyl acetate, often derived from sugarcane, known for a sweet, smooth cup.
- Espresso A small, intense coffee forced through fine grounds under about 9 bar of pressure.
- Excelsa A liberica variant prized for tart, fruity, layered flavors; a very small share of global coffee production.
- Extraction yield (EY) The percent of ground coffee mass dissolved into the cup; the ideal window is roughly 18 to 22 percent.
F
- Fermentation Microbial breakdown of the sugary mucilage and fruit that develops flavor in green coffee, or ruins it if uncontrolled.
- Fines The smallest particles produced by grinding; they boost body but can clog flow and over-extract.
- First crack The audible popping early in roasting as beans expand and release moisture; the threshold of a drinkable light roast.
- Flash brew (Japanese iced) Hot pour-over brewed directly onto ice, locking in aromatics for a bright, clean iced coffee.
- Flat burr A burr set with two parallel ring-shaped burrs facing each other; prized for a tight, uniform grind and cup clarity.
- Flat white Espresso with steamed milk and thin microfoam; smaller and stronger-tasting than a latte.
G
- General hardness (GH) The calcium and magnesium content of brew water, the minerals that actively pull flavor from the grounds.
- Gesha (Geisha) A celebrated arabica variety famous for jasmine-bergamot florals and record auction prices, especially from Panama.
- Gooseneck kettle A kettle with a long, curved spout that gives you a slow, controlled stream for precise pour-over brewing.
- Green coffee Unroasted coffee beans, as traded and stored before they are roasted into the brown beans you brew.
H
- Hard water Water high in dissolved calcium and magnesium; good minerals aid extraction, but excess scales machines.
- Headspace The empty room above the coffee or water in a brewer or kettle that affects pouring and brew dynamics.
- Honey process Drying the bean with some sticky fruit layer left on, landing in sweetness and body between washed and natural.
- Hulling Removing the dried parchment (or dried fruit) from a coffee seed to reveal the green bean ready for sale.
I
K
L
- Latte Espresso with lots of steamed milk and a thin layer of foam.
- Liberica A minor coffee species with large irregular beans and a smoky, jackfruit-like profile; known as barako in the Philippines.
- Light roast A roast stopped near first crack: bright, acidic, origin-expressive, with a dry surface and no oil.
- Long black Espresso poured over hot water (order matters), preserving crema; the antipodean americano.
- Lungo A longer espresso pulled with more water for a larger, lighter shot.
M
- Macchiato Espresso "stained" with a small dab of milk foam; not the large syrupy cafe-chain version.
- Maillard reaction Heat-driven reactions between sugars and amino acids during roasting that build savory, toasty, complex brown flavors and aromas.
- Medium roast A balanced roast with caramel sweetness, moderate acidity and body: the everyday middle ground.
- Microlot A small, separately processed and traceable batch of coffee, often from a single farm or plot.
- Mocha (caffe mocha) A latte with chocolate; also a historic name for coffee shipped from the Yemeni port of Mocha.
- Moisture content The water percentage in green coffee; roughly 10 to 12 percent is the storage sweet spot.
- Mouthfeel The tactile sensation of coffee in your mouth: its weight, texture, and whether it feels smooth or drying.
- Mucilage The sticky, sweet fruit layer clinging to the bean; how much is left on largely defines the process.
N
O
P
- Pacamara A large-beaned Pacas x Maragogipe cross with bold, complex, sometimes wild flavors, bred in El Salvador.
- Parchment The papery hull protecting the green bean during drying and storage, removed by hulling before export.
- Peaberry A single rounded bean that forms when only one of a cherry's two seeds develops; often sorted and sold separately.
- Percolation Water passing through a bed of grounds, as in pour-over, drip, or espresso; flow rate shapes the cup.
- Percolator An old stovetop brewer that recirculates boiling water through the grounds, often tasting bitter.
- Phin A small Vietnamese metal drip filter that brews strong coffee slowly, classically over sweetened condensed milk.
- Piccolo A small milk drink: a ristretto or espresso topped with a little steamed milk in a small glass.
- Polishing An optional step that buffs residual silverskin off hulled green beans to give a cleaner, more uniform look.
- Portafilter The handled device that holds the basket of grounds and locks into an espresso machine's group head.
- Pre-infusion A gentle low-pressure wetting before full pressure, helping the puck settle and reducing channeling.
- Puck The compressed disc of ground coffee inside the portafilter basket that water is forced through.
Q
R
- Raised drying bed A mesh table raised off the ground that dries cherries or parchment with even airflow from all sides.
- RDT (Ross Droplet Technique) Adding a drop or two of water to beans before grinding to cut static and retention.
- Refractometer A small device that measures the dissolved solids in a brew so you can calculate its strength and extraction yield.
- Ristretto A shorter, more concentrated espresso pulled with less water and yield than a standard shot.
- Roast date The day the beans were roasted: the freshness clock that matters far more than a best-before date.
- Roast level How far a coffee was roasted, from light to dark, which shapes its acidity, body, sweetness, and roast flavor.
- Robusta The hardy coffee species: stronger and more bitter, roughly double the caffeine, heavier crema, usually cheaper.
S
- SCA (Specialty Coffee Association) The trade body behind the cupping protocol, flavor wheel, and brewing standards cited across specialty coffee.
- Second crack A later, quieter, faster crackle in roasting as the bean's structure breaks down and oils surface; the door to dark roasts.
- SHB / SHG Altitude-based green coffee grades implying denser, higher-quality beans.
- Silverskin The thin seed membrane on a coffee bean that dries, loosens, and flakes off as chaff during roasting.
- Siphon (vacuum pot) A two-chamber vapor-pressure immersion brewer that gives a clean, aromatic, full-flavored cup.
- SL28 and SL34 Kenyan-selected arabica varieties behind the classic blackcurrant brightness and structured acidity of Kenyan coffee.
- Slurry The mixture of ground coffee suspended in water during brewing, before it drains or is separated.
- Strength How concentrated the brew tastes, set by dissolved solids and ratio; distinct from how much was extracted.
- Sweetness A pleasant impression of sugar or ripe fruit in coffee; a hallmark of well-grown, well-processed beans.
- Swiss Water Process A solvent-free decaffeination method using water and activated carbon that preserves flavor well.
T
- Tamper The hand tool used to press ground coffee in the basket into a level, firm puck before pulling a shot.
- TDS (total dissolved solids) The percentage of dissolved coffee in your cup; the measurable definition of strength.
- Terroir The combined effect of place (soil, altitude, climate) on how a coffee tastes.
- Turkish coffee (ibrik/cezve) Very finely ground coffee simmered with water and often sugar, served unfiltered with the grounds in the cup.
- Typica One of the two great arabica lineages: clean and sweet in the cup, but lower-yielding and disease-prone.
U
V
W
- Washed A process that removes the fruit and ferments off the sticky layer before drying, giving clean, bright cups.
- Water activity A 0 to 1 measure of how available the water in green coffee is, affecting shelf life and stability.
- WDT (Weiss Distribution Technique) Stirring dry espresso grounds with thin needles to break clumps for even extraction.