Asinine means extremely foolish or stupid in a way that makes people shake their heads in disbelief. When someone makes an asinine decision, they're doing something so obviously unwise that others wonder how they could have thought it was a good idea, like choosing to sled down a hill covered in rocks or trying to pet a wild porcupine.

The word comes from the Latin word for donkey, an animal once considered particularly stubborn and dim-witted. An asinine idea shows a complete lack of common sense or basic judgment. If your friend suggests using gasoline to start a campfire, or if a character in a story tries to swim across a lake during a thunderstorm, those would be asinine choices.

You might hear someone dismiss a ridiculous argument as asinine, or describe a plan as utterly asinine when it ignores obvious problems. The word carries real force. It's stronger than calling something merely silly or dumb. When you call something asinine, you're saying it's so foolish that it's almost insulting to everyone's intelligence.

Notice that asinine describes ideas, decisions, and statements rather than people themselves. A smart person can still make an asinine choice when they're not thinking clearly.