your eyes nearly pop out of your head

your eyes nearly pop out of your ˈhead

(informal) somebody has an expression of great surprise on their face: Our eyes nearly popped out of our heads when we saw a giraffe walking down the High Street. ▶ ˈeye-popping adj. (informal) very surprising or amazing: a movie with eye-popping special effects
See also: eye, head, nearly, of, out, pop