A wank
When a guy stands in front of a girl and just jiggles around like he's trying to get her to notice him, and he says 'wank wank' like it's some kind of secret code.
He stood in front of me and said 'wank wank' like he was a secret agent.
My friend did a wank wank in front of the whole class.
He did a wank wank and then walked away like he was cool.