Grind Size
研磨度
GrindingDefinition
The average particle diameter of ground coffee, set by the gap between the grinder's burrs or by how long a blade grinder runs. It is the single most powerful variable a brewer controls: finer grounds expose more surface area and slow the flow of water, speeding extraction, while coarser grounds do the opposite. Every brew method has a working range - espresso near 200 microns, filter coffee roughly 400 to 800, French press beyond 1000.
Etymology
Grind comes from the Old English grindan, to rub together or crush; size became a standard label in coffee retail only in the mid-20th century, as roasters began printing brew-specific directions on bags.
In use
The first dial a barista touches when a shot runs too fast or too slow - 'the grind was too coarse' explains a gushing espresso in three words.