Funny is an adjective that describes something causing laughter or amusement.
But wait, there's more! Funny can also mean:
1. Strange or unusual (That's funny, I could have sworn I left my keys here)
2. Slightly unwell (I feel a bit funny today)
3. Clever in a tricky way (He's got a funny way of solving problems)
4. In American slang, it can mean "interesting" or "cool" (That new game is pretty funny)