To rebel means to resist or fight against authority, rules, or the way things are supposed to be. When colonists rebelled against British rule in 1776, they refused to follow laws they believed were unjust. When students rebel against a strict dress code by wearing forbidden clothing, they're deliberately challenging the rules.

A rebel (the noun) is someone who refuses to accept control or follow established customs. Robin Hood was a rebel who defied the Sheriff of Nottingham. In The Lion, the Witch and the Wardrobe, Edmund rebels against his siblings by sneaking off to visit the White Witch.

Rebellion can be serious, like fighting against an oppressive government, or everyday, like a teenager rebelling against a curfew. Some rebels change history by standing up for what's right, like the suffragettes who rebelled against laws that prevented women from voting. Others rebel simply because they dislike being told what to do.

The word can also describe things that don't cooperate: a rebel strand of hair that won't stay in place, or a rebel cookie that crumbles when all the others hold their shape. When your body rebels against something you ate, it means your stomach is rejecting it.

Not all rebellion is good or bad; it depends on what you're fighting against and why.