Over your head

Meaning

If something goes over your head, you don't understand it, usually because it's too complicated, too technical or too clever. The picture is a ball flying high above you: you see it go by, but you can't catch it. Jokes often go over people's heads, and so do lectures, legal documents and conversations full of jargon.

It is informal and very common. Saying it about yourself is honest and a little modest: "Honestly, that went over my head." Saying it about someone else can sound superior, as if they're not smart enough: "The joke went right over his head." Be careful using it about a person who is in the room. There's a second use, "in over your head", which means you are in a situation that's too difficult for you, like a swimmer in water that's too deep.