Insufferable means unbearably annoying or impossible to tolerate. When someone is insufferable, their behavior is so irritating, arrogant, or obnoxious that you can barely stand being around them.

Picture a classmate who constantly brags about every good grade, interrupts others to correct tiny mistakes, and acts like they know everything. That's insufferable behavior. Or imagine someone who complains endlessly about minor problems while ignoring that others have real difficulties. The word captures that feeling when someone's personality or actions become so frustrating that you want to leave the room.

You might describe a movie villain as insufferable when they're not just evil but also pompous and annoying. A character in a story might be insufferable before learning an important lesson about humility.

What makes someone insufferable isn't usually one big thing but rather a pattern of small, grating behaviors. The insufferable person often lacks self-awareness, not realizing how their actions affect others. Interestingly, people sometimes become insufferable when they're actually insecure and overcompensating by showing off or putting others down.