To be condescending means to treat someone as if they're less intelligent or less important than you are. When someone speaks condescendingly, they use a tone or words that suggest they think they're superior, even if they pretend to be helpful or friendly.

Imagine a classmate who explains something you already understand, talking to you slowly and using baby words, acting like you couldn't possibly grasp it otherwise. That's condescending behavior. Or picture someone saying “Good job!” in a way that sounds like they're praising a toddler for tying their shoes, when you've actually accomplished something genuinely difficult.

Condescending people act like they're doing you a favor just by paying attention to you.

Teachers sometimes worry about sounding condescending when they explain things, because there's a fine line between being genuinely helpful and treating students like they can't think. The key difference: someone who's truly helpful respects your intelligence and meets you where you are. Someone who's condescending assumes you're beneath them and makes sure you feel it. You can usually hear condescension in someone's voice, that sticky-sweet tone that feels more insulting than honest criticism would be.