Feisty describes someone who is lively, spirited, and quick to stand up for themselves, especially when you might not expect it. A feisty person has energy and courage that bursts out when challenged.

You might call a small dog feisty if it barks boldly at much larger dogs, or describe your grandmother as feisty if she playfully argues with anyone who underestimates her. A feisty debate team member jumps eagerly into arguments, defending their position with spirit and confidence. The word often applies to people or animals who are small or seem mild but surprise you with their boldness and determination.

Feisty isn't quite the same as aggressive. Someone feisty has spark and attitude, but usually in a way that's spirited rather than mean. When a younger student stands up to a classroom bully with quick words and refuses to back down, that's feisty. When your little sister won't let you win at chess without a real fight, matching your every move with determination, she's being feisty.

The word carries a sense of admiration. Calling someone feisty usually means you respect their spirit and energy, even if they're occasionally challenging to deal with.