Prim means excessively proper, formal, or precise in behavior and appearance, often to the point of seeming stiff or uptight. A prim person sits up perfectly straight, speaks in careful, measured tones, and wouldn't dream of getting messy or acting silly.

Picture a student who always keeps their desk spotlessly organized, never laughs too loudly, and corrects other people's grammar even during casual conversations. Or imagine someone at a picnic who fusses about grass stains and won't join the fun because they might wrinkle their clothes. That's being prim.

The word often carries a hint of criticism. While there's nothing wrong with being neat and polite, someone who's prim takes it too far, caring more about perfect appearances than enjoying life. A prim teacher might get upset about a loosened tie or an untucked shirt, even when students are working hard. A prim aunt might gasp at children playing in the mud, even though that's what kids do.

You'll also hear prim and proper as a phrase describing someone particularly concerned with strict manners and appearances. Being appropriately neat and respectful matters, but being so prim that you can't relax or have fun can miss the point entirely.