hide (one's) head
To lower one's head or cover one's face, typically due to embarrassment or shame. Michael showed me exactly who had broken my vase when he hid his head in response to my question. I totally forgot to do my homework, so all I could do was hide my head as my teacher collected it from everyone else.
hide the sausage
rude slang To have sexual intercourse. A: "Did you two hide the sausage last night?" B: "Well that's a personal question!"