Biting, a.
That bites; sharp; cutting; sarcastic; caustic. "A biting affliction." "A biting jest." Shak.
Shades of meaning
Fernald has no entry of its own for biting; he lists it under bitter.
Where he writes about it:
We say a sour face, sharp words, bitter complaints, caustic wit, cutting irony, biting sarcasm, a stinging taunt, harsh judgment, a tart reply. — from bitter
Tart and sharp utterances may not proceed from an intention to wound, but merely from a wit recklessly keen; cutting, stinging, and biting speech indicates more or less of hostile intent, the latter being the more deeply malicious. — from bitter