Glossary
Coffee, defined.
Every term worth knowing, in plain language — our own wiki. New to good coffee or deep in the rabbit hole, look it up here. Search, or browse by topic.
64 terms
A
- AcidityTasting
- The bright, tangy liveliness in a cup — the good kind, like biting into fruit, not sourness from a bad brew. It's a feature of quality coffee, not a flaw.See also: Sweetness, Washed process, Balance
- AeroPressGear
- A plunger-style brewer that combines immersion steeping with a pressed finish through a paper filter. Forgiving, fast, near-indestructible — the reason it's the default travel brewer.See also: Immersion vs percolation, French press, Filter
- AftertasteTasting
- What lingers after you swallow, also called the finish. A long, pleasant aftertaste is a mark of quality; a short or harsh one tells you something's off.See also: Tasting notes, Balance, Body
- AgitationBrewing
- Any stirring, swirling, or pour turbulence that mixes water and grounds. More agitation speeds extraction and evens it out — a lever most people ignore and then wonder why their cup is inconsistent.See also: Extraction, Pour-over, Channeling
- AgtronRoasting
- A numbered scale from a spectrophotometer that reads roast color objectively — lower numbers are darker. Roasters use it to make "medium" mean the same thing every batch instead of eyeballing it.See also: Roast level, Development time
- AltitudeBeans & sourcing
- Higher-grown coffee matures slower in cooler air, which builds denser beans with more acidity and complexity. It's why you'll see numbers like "1,800 masl" on a bag — it's a quality signal.See also: Origin, Terroir, Acidity
- ArabicaBeans & sourcing
- The species behind nearly all specialty coffee — more delicate, more aromatic, and fussier to grow than robusta. Robusta is hardier and higher in caffeine but usually flatter and more bitter.See also: Varietal, Origin, Bitterness
B
- BalanceTasting
- How well acidity, sweetness, bitterness, and body hold together without one shouting over the rest. A balanced cup doesn't have to be exciting, but nothing in it feels off.See also: Acidity, Sweetness, Body
- BitternessTasting
- A sharp, harsh taste that's fine in small doses but dominates when coffee is over-extracted or roasted dark. If your cup is aggressively bitter, look at grind, time, and roast before blaming the beans.See also: Extraction, Fines, Roast level
- BlendBeans & sourcing
- Two or more coffees combined for a flavor the components can't hit alone — usually for balance, body, or year-round consistency. Good blends are designed, not just leftovers swept together.See also: Single origin, Body, Balance
- BloomBrewing
- The first small pour that wets the grounds and lets trapped CO2 escape — you'll see it bubble and swell. Skipping it leaves gas in the bed that blocks even extraction; 30–45 seconds is plenty.See also: Degassing, Pour-over, Extraction
- BodyTasting
- How heavy or full the coffee feels in your mouth — think skim milk versus cream. Naturals and darker roasts tend to feel heavier; washed light roasts feel more delicate.See also: Mouthfeel, Natural process, Balance
- Burr grinderGrinding
- A grinder that crushes beans between two rotating burrs to a consistent, adjustable size — as opposed to a blade grinder, which just chops unevenly. If you upgrade one thing, upgrade to this.See also: Grind size, Fines, Distribution
C
- ChaffRoasting
- The papery skin that flakes off beans during roasting. Harmless, mostly blown away in commercial roasters, and the reason your home popcorn-popper roast makes a mess.See also: Green coffee, First crack
- ChannelingBrewing
- When water carves a fast path through the coffee bed instead of soaking it evenly, over-extracting one spot and skipping the rest. Uneven grinding, poor distribution, or a sloppy tamp cause it.See also: Distribution, Tamp, Extraction
- CremaEspresso
- The reddish-brown foam on top of a fresh shot, made of CO2 emulsified with oils. A sign of fresh coffee and pressure — but not, on its own, proof the shot tastes good.See also: Shot, Degassing, Pre-infusion
- Cup scoreBeans & sourcing
- A 0–100 quality grade from trained tasters; roughly 80+ counts as specialty. It's a useful shorthand for quality, not a ranking of what you'll personally enjoy.See also: Cupping, Defect, Green coffee
- CuppingTasting
- The standardized way pros taste and score coffee: steep grounds in hot water, break the crust, and slurp from a spoon. It levels the playing field so coffees are judged the same way.See also: Cup score, Tasting notes, Defect
D
- DefectTasting
- An off-flavor or fault — ferment, mold, phenol, potato — usually traced to bad processing or storage. One defective bean can taint an entire cup, which is why sorting matters.See also: Cupping, Cup score, Green coffee
- DegassingRoasting
- Fresh-roasted coffee keeps venting CO2 for days after the roast. Brew too soon and the gas fights even extraction; most coffee hits its stride a few days to two weeks off roast.See also: Bloom, First crack, Extraction
- Development timeRoasting
- The stretch between first crack and dropping the beans, where flavors round out and raw, grassy notes burn off. Too short and it tastes sour and thin; too long and origin character flattens.See also: First crack, Roast level, Maillard reaction
- DistributionGrinding
- How evenly the grounds are spread — in an espresso puck or across a pour-over bed — before water hits. Uneven grounds send water down the path of least resistance and extract unevenly.See also: Channeling, Tamp, Puck
- DoseEspresso
- The weight of ground coffee in the basket, in grams. It's one leg of the espresso recipe — dose in, yield out, over a target time.See also: Yield, Shot, Ratio
- DrawdownBrewing
- The final phase of a pour-over as the last water drains through the bed. A very slow drawdown often means the grind's too fine or fines have clogged the filter.See also: Pour-over, Grind size, Fines
- DripperGear
- The cone or flat-bottom brewer that holds the filter and grounds for a pour-over — V60, Kalita, and the like. Shape and hole size change how water flows, which changes how the cup tastes.See also: Pour-over, Filter, Gooseneck kettle
E
- ExtractionBrewing
- The act of dissolving flavor out of the grounds and into the water. Under-extract and it's sour and thin; over-extract and it's bitter and hollow; the sweet spot sits in between.See also: Extraction yield, Grind size, TDS
- Extraction yieldScience & measurement
- The percentage of the coffee's mass that actually dissolved into your cup, typically targeted around 18–22%. Below that trends sour, above it trends bitter — it's the number behind "under-" and "over-extracted."See also: Extraction, TDS, Refractometer
F
- FilterGear
- What separates grounds from your coffee — paper traps oils and fines for a cleaner, brighter cup; metal lets them through for more body and texture. Neither is "better"; they make different coffee.See also: Dripper, French press, Mouthfeel
- FinesGrinding
- The dust-fine particles every grinder produces alongside the target size. A few help body; too many over-extract and muddy the cup, and they're the usual suspect behind bitterness.See also: Grind size, Burr grinder, Bitterness
- First crackRoasting
- An audible pop, like popcorn, when moisture inside the bean flashes to steam and the bean expands. It marks the start of a drinkable roast — everything before is underdeveloped.See also: Second crack, Development time, Roast level
- French pressGear
- A full-immersion brewer where grounds steep in water, then a metal mesh plunger separates them. Simple and full-bodied, with some sediment in the cup because the metal filter lets oils and fines through.See also: Immersion vs percolation, Filter, Body
G
- Gooseneck kettleGear
- A kettle with a long, narrow spout that gives you precise control over where and how fast water pours. Close to non-negotiable for pour-over; overkill for a French press.See also: Pour-over, Temperature, Dripper
- Green coffeeBeans & sourcing
- Raw, unroasted coffee seeds — dense, grassy, and shelf-stable for months. Everything a roast becomes is already latent in the green; roasting just develops it.See also: Roast level, Origin, Cup score
- Grind sizeGrinding
- How coarse or fine you grind, which sets how fast water pulls flavor from the coffee. It's the biggest dial you have at home: finer extracts faster, coarser slower.See also: Extraction, Burr grinder, Fines
H
- Honey processBeans & sourcing
- A middle path: the skin comes off but some sticky fruit mucilage stays on during drying. It splits the difference between washed and natural — more sweetness and body than washed, more clarity than natural.See also: Washed process, Natural process, Sweetness
I
- Immersion vs percolationBrewing
- Two ways to brew: immersion steeps grounds in water then separates them (French press); percolation flows water through a bed (pour-over). Immersion is forgiving; percolation gives more control.See also: Pour-over, French press, Drawdown
L
M
- Maillard reactionRoasting
- The heat-driven reaction between sugars and amino acids that builds most of coffee's brown color, aroma, and savory-sweet complexity. Same chemistry that browns toast and seared steak.See also: Development time, Roast level, Sweetness
- MouthfeelTasting
- The physical texture of the coffee — silky, syrupy, tea-like, gritty. Closely tied to body, but specifically about how it feels rather than how much of it there is.See also: Body, Filter, Aftertaste
N
- Natural processBeans & sourcing
- Beans dry inside the whole cherry, so the fruit's sugars soak in as they go. Expect heavier body and bold, jammy, sometimes boozy fruit — less clean than washed, more flavor-forward.See also: Washed process, Honey process, Body
O
- OriginBeans & sourcing
- Where a coffee was grown — country, region, and often the specific farm or washing station. It's the single biggest lever on how a coffee tastes before anyone touches a roaster.See also: Terroir, Single origin, Altitude
P
- PortafilterEspresso
- The handled basket holder that locks into the espresso machine and carries the puck. The thing you're holding when you look like you know what you're doing.See also: Puck, Tamp, Shot
- Pour-overBrewing
- A percolation method where you pour hot water over grounds in a filter and let gravity do the rest. Slow, controllable, and the clearest way to taste a light roast's detail.See also: Dripper, Gooseneck kettle, Immersion vs percolation
- Pre-infusionEspresso
- A gentle, low-pressure wetting of the puck before full pressure kicks in. It settles the bed and reduces channeling, giving a more even extraction.See also: Puck, Channeling, Extraction
- PuckEspresso
- The compacted disc of grounds in the portafilter that water is forced through. A clean, even puck is the whole game in espresso; a cracked or channeled one wrecks the shot.See also: Tamp, Portafilter, Channeling
R
- RatioBrewing
- The weight of coffee to water, written like 1:16 (one gram coffee to sixteen grams water). It's your starting recipe — tighten it for a stronger cup, widen it for a lighter one.See also: TDS, Extraction, Scale
- RDTGrinding
- Ross Droplet Technique: a spritz of water on the beans before grinding to knock down the static that flings grounds and clumps. Cheap fix, noticeably less mess.See also: Fines, Burr grinder, Grind size
- RefractometerScience & measurement
- A small device that measures TDS by reading how light bends through a drop of coffee. It turns "tastes strong" into a number, which is how you make a good cup repeatable.See also: TDS, Extraction yield, Extraction
- RistrettoEspresso
- A "restricted" shot pulled with less water than standard, so a lower yield for the same dose. Denser and often sweeter, with less of the harsh tail-end extraction.See also: Yield, Lungo, Shot
- Roast levelRoasting
- How far a coffee is roasted, from light to dark — a spectrum, not fixed grades. Lighter keeps more origin character and acidity; darker trades that for body and roast flavor.See also: First crack, Second crack, Agtron
S
- ScaleGear
- A gram scale, ideally with a timer, that lets you weigh coffee and water instead of guessing with scoops. The cheapest upgrade that makes your coffee repeatable — buy one before a fancier grinder.See also: Ratio, Dose, Yield
- Second crackRoasting
- A quieter, sharper crackle later in the roast as the bean's structure breaks down and oils migrate to the surface. Roast into or past it and you're in dark-roast territory.See also: First crack, Roast level, Development time
- ShotEspresso
- A single serving of espresso pulled by forcing hot water through a compacted puck under pressure. Everything else on an espresso menu is a shot plus milk or water.See also: Dose, Yield, Crema
- Single originBeans & sourcing
- Coffee from one place — a single country, region, or farm — rather than blended across origins. You drink it to taste a specific place, not a consistent house flavor.See also: Blend, Origin, Terroir
- SweetnessTasting
- The natural sugar-like quality of a well-grown, well-roasted, well-brewed coffee — no sugar added. It's often the first thing that disappears when any step goes wrong.See also: Acidity, Balance, Maillard reaction
T
- TampEspresso
- Pressing the grounds into a level, compact puck before pulling the shot. Consistency matters more than brute force — an uneven tamp invites channeling.See also: Puck, Distribution, Channeling
- Tasting notesTasting
- The flavors a coffee reminds tasters of — "blueberry," "cocoa," "jasmine." They're honest comparisons, not added ingredients; nobody put blueberries in your coffee.See also: Cupping, Aftertaste, Origin
- TDSBrewing
- Total dissolved solids — the percentage of your cup that's actually dissolved coffee, i.e. its strength. Filter coffee usually lands around 1.2–1.5%; espresso is far higher.See also: Refractometer, Extraction yield, Ratio
- TemperatureScience & measurement
- Brew water is usually 90–96°C — hotter extracts faster and can push bitterness, cooler under-extracts and leaves it sour. A rare case where "just off the boil" is genuinely good advice.See also: Extraction, Gooseneck kettle, Bitterness
V
W
- Washed processBeans & sourcing
- The fruit is stripped off and the beans are fermented and rinsed in water before drying. It tends to produce a cleaner, brighter, more acidic cup where the origin's character shows through.See also: Natural process, Honey process, Acidity
- Water hardnessScience & measurement
- The mineral content of your brewing water, mostly magnesium and calcium. Minerals help pull flavor out of coffee, so pure distilled water actually brews flat — but too hard scales up your machine.See also: TDS, Extraction, Temperature