Acidity

Etymology

From Latin "acidus" (sour), from "acere" (to be sour) and akin to "acer" (sharp). That sharp-edged root runs through a family of words, including "acrid," "acute," and "acumen" — all carrying the sense of something keen.

noun · /uh-SID-ih-tee/
The bright, sour, mouth-watering quality that acids like citrus, vinegar, and wine bring to food.
What it names
The element cooks reach for to “wake up” a dish — the sharpness that balances richness, salt, and sweetness.
Example
The stew tasted flat until a squeeze of lemon added the acidity it was missing.
Related idea
Distinct from astringent: acidity is a sour taste that makes you salivate, while astringency is a drying, puckering feel — dishes often need acidity, but rarely want astringency.