Derisive means mocking or scornful, showing contempt through ridicule. When someone laughs in a derisive way, they're not laughing with you but at you, making fun of what you've said or done. A derisive comment isn't gentle teasing between friends: it's meant to belittle or dismiss.

Imagine presenting your science project idea and hearing someone snort and say “Yeah, that'll work” in a sneering tone. That's derisive. The person isn't offering constructive criticism or asking honest questions. They're trying to make your idea seem foolish.

Derisive laughter, remarks, or looks all share this quality of contempt. When a crowd responds with derisive jeers to a politician's speech, they're showing open scorn, not respectful disagreement. When someone makes a derisive gesture, like rolling their eyes dramatically, they're communicating “this is beneath me” or “you're ridiculous.”

Related words include derision (the noun form) and deride (the verb). If someone derides your efforts, they're being derisive about them.