Synonyms for Acrimonious:

adj.

all (adjective)
bitter.
hard (adjective)
stern.
irritable (adjective)
cross, cantankerous, irascible, churlish, spiteful, tart, petulant, acerbic, huffy, irritable, bearish, crusty, crabbed, peevish, bitter, touchy, snappish, caustic, prickly, acid, cranky, petty, sour, bellicose, surly.
nasty in behavior, speech (adjective)
cranky, acid, spiteful, acerbic, censorious, sharp, cutting, sarcastic, churlish, caustic, cross, irascible, tart, rancorous, angry, peevish, astringent, petulant, bitter.
resentful (adjective)
rancorous.
severe (adjective)
rigid, ascetic, harsh, draconian, cutting, rigorous, frosty, prudish, intolerant, sharp, short, censorious, precise, obstinate, demanding, imperial, cool, stringent, hidebound, critical, brisk, spare, authoritarian, acute, lean, spartan, exacting, astringent, uncompromising, stern, gruff, intense, grim, icy, raw, stiff-necked, oppressive, austere, dour, disciplined, relentless, piquant, caustic, fundamental, blunt, keen, abrupt, stark, inflexible, obdurate, acerbic, tart, dry, severe, curt, meticulous, chilly, brusque, bleak, strict, correct, puritanical, strait-laced, basic, crisp, unbending.
sharp (adjective)
rancorous, angry, sharp, sarcastic.

n.

unforeseen, stormy, in the wrong place at the wrong time, uneasy, one thing after another, it's not someone's day, Houston, we have a problem, trouble is brewing (for), the matter. hard, embittered, love, attitude, rancorous. acrimonious (noun)
bitter, resentful.

Other synonyms:

stormy, rancorous, unforeseen, uneasy. hard. bitter
embittered.
scornful
sarcastic.
Other relevant words:
resentful, angry, stormy, rancorous, unforeseen, uneasy, sarcastic, embittered, hard.

Usage examples for acrimonious

  1. After speaking of the gloomy conditions in the Socialist Party abroad, he thus comments on conditions in the American branch of the international organization: " All the more unfortunate is it that the energies of the Socialist Party should at this time be dissipated in acrimonious and fruitless controversies brought on by the self- styled Left Wing movement. – The Red Conspiracy by Joseph J. Mereto
  2. This landed him in fresh mortification, for the pastor disavowed the libel, Rousseau declined to accept the disavowal, and sensible men were wearied by acrimonious declarations, explanations, protests. – Rousseau Volumes I. and II. by John Morley