Synonyms for Acerbic:

adj.

bitter, sharp, or sour (adjective)
astringent, acidic, acrid, caustic, tart, harsh, sharp.
irritable (adjective)
huffy, tart, irascible, caustic, crusty, cranky, touchy, bearish, spiteful, petulant, petty, acrimonious, surly, cross, acid, crabbed, bellicose, sour, snappish, churlish, prickly, irritable, cantankerous, peevish, bitter.
resentful (adjective)
irritated, envious, malevolent, resentful, vexed, embittered, galled, bitter, Piqued, Huffed, vindictive, infuriated, antagonistic, Spleenful, splenetic, hurt, stung, miffed, discontent, spiteful, sore, offended.
severe (adjective)
oppressive, ascetic, puritanical, austere, obdurate, dour, relentless, intolerant, censorious, intense, lean, harsh, astringent, imperial, raw, stiff-necked, acute, icy, unbending, strict, stringent, gruff, correct, blunt, inflexible, tart, stark, fundamental, frosty, chilly, authoritarian, uncompromising, severe, exacting, prudish, rigid, piquant, meticulous, bleak, hidebound, acrimonious, abrupt, brusque, crisp, precise, caustic, strait-laced, demanding, rigorous, grim, brisk, keen, spartan, cutting, disciplined, spare, critical, obstinate, sharp, curt, cool, dry, draconian, basic, short, stern.
sharp (adjective)
sharp.
sour (adjective)
acetous, acidic, acerb, unripe, sharp, piquant, sour, bitter, tart, pungent.

n.

accusatory, accusing, ad hominem. sarcastic. taste. tangy, acetous. scathing, stinging, truculent, mordacious, attack, trenchant, respect, slashing. acerbic (noun)
caustic, acrid, vitriolic, acid, sour, blistering, sharp, sulphurous, venomous, bitter, virulent, astringent, sulfurous, acerb, unpleasant.

Other synonyms:

acetous, accusatory, accusing, ad hominem, tangy, mordacious, stinging. slashing, scathing. truculent, trenchant. Other relevant words:
slashing, virulent, tangy, sulphurous, accusing, respect, scathing, vitriolic, mordacious, acrid, trenchant, sarcastic, attack, taste, unpleasant, blistering, venomous, acetous, stinging, sulfurous, acerb, truculent, accusatory.