Synonyms for Trenchant:

adj.

•acid (adjective)
mordant.
•all (adjective)
searching.
•blunt (adjective)
explicit.
•effective (adjective)
forcible.
•intelligent (adjective)
incisive.
•sarcastic, scathing (adjective)
effective, pointed, mordant, pungent, critical, emphatic, sententious, significant, weighty, acid, clear, penetrating, caustic, keen, clear-cut, cutting, strong, dynamic, acerbic, impressive, sharp, intense, severe, biting, forcible, distinct, unsparing, vigorous, incisive, effectual, salient, explicit, astringent, crisp, graphic, acute.
•sharp (adjective)
sharp.
•succinct (adjective)
pithy.

n.

careful, penetrating, acute, sensitive, perceptive. attack, mordant, vitriolic, respect, corrosive, acerbic, stinging, astringent, acid, scathing, acrid, acidic, slashing, truculent, mordacious. •trenchant (noun)
clear, searching, distinct, intelligent, hard-hitting, efficacious, effective, effectual, clear-cut.

Other synonyms:

critical, mordacious, acidic, emphatic, astringent, stinging. cutting, mordant, corrosive, scathing, slashing, vitriolic, caustic. biting, penetrating, acrid, keen, acute, pungent. acid, truculent, sensitive. pointed, acerbic. perceptive. sharp.

Usage examples for trenchant

1. Then they ride to meet each other, and strike upon each other's shield great blows with their sharp and trenchant swords. – Four Arthurian Romances "Erec et Enide", "Cliges", "Yvain", and "Lancelot" by Chretien DeTroyes

2. Asher Israelit, less trenchant but equally effective, exhorted crowds to repentance. – The Haskalah Movement in Russia by Jacob S. Raisin