ETYM Latin acrimonia, from acer, sharp: cf. French acrimonie.
1. A quality of bodies which corrodes or destroys others; also, a harsh or biting sharpness.
2. Sharpness or severity, as of language or temper; irritating bitterness of disposition or manners.

ETYM AS. biternys; biter better + -nys = -ness.
1. A sharp and bitter manner; SYN. acrimony, acerbity, jaundice.
2. The property of having a harsh unpleasant taste; SYN. bitter.