waspish
Quick to speak in a sharp, mean, stinging way.
Waspish describes someone who speaks or acts in a sharp, irritable, bad-tempered way, like they're ready to sting with their words. Just as a wasp might buzz around aggressively and attack when annoyed, a waspish person makes snappy, cutting remarks that can hurt feelings.
A waspish teacher might respond to a student's question with, “If you'd been paying attention, you'd already know that.” A waspish comment at the dinner table might be, “Some of us actually helped cook, unlike certain people.” These remarks have a stinging quality, meant to hurt or criticize.
The word suggests more than simple anger or frustration. Someone having a bad day might snap once, but a waspish person has a consistent sharpness to their tone, an edge that makes others cautious around them. You might describe someone's waspish tone of voice or their waspish sense of humor (humor that targets and stings others).
People often become waspish when they're feeling defensive, tired, or frustrated themselves, even if they don't mean to.