Absurd means ridiculously unreasonable or impossible, so illogical that it's almost laughable. When your little brother insists he can fly by flapping his arms, that's an absurd claim. When someone suggests finishing a 500-page book in five minutes, that's an absurd expectation.

Something absurd goes beyond just being wrong or unlikely. It contradicts common sense so completely that it seems silly. If a friend seriously argued that dogs should drive cars or that the moon is made of Swiss cheese, you'd recognize these ideas as absurd. The word captures that feeling when something is so far from reality that you can barely take it seriously.

You might encounter absurd rules that make no sense, like a sign saying “No standing while sitting” or a law requiring fish to have fishing licenses. Sometimes situations become absurd through layers of confusion: imagine a substitute teacher who doesn't speak English teaching a French class to students who only speak Spanish.

The related noun is absurdity. When something reaches a level of absurdity, it has become so unreasonable that people can only shake their heads in disbelief. The absurdity of a situation often becomes clear when you try explaining it to someone else and realize how ridiculous it sounds.