I . a.
1.
Acid, tart, pricked, sharp, acetous, acetose.
2.
Cross, crabbed, morose, acrimonious, currish, surly, testy, touchy, cantankerous, crusty, fretful, peevish, petulant, pettish, snappish, waspish, snarling, cynical, froward, uncivil, rude, rough, harsh, ill-tempered, ill-natured, austere.
3.
Bitter, unpleasant, disagreeable.
4.
Gloomy, sad, dismal, morose, discontented, austere.
5.
Rancid, musty, spoiled, bad, coagulated, turned, curdled, loppered.
II . v. a.
1.
Make acid, turn ~.
2.
Imbitter, make unpleasant.
III . v. n.
Turn ~, become acid.