crack the whip 

slapping a girl in the face after she sucks your cock

I had to crack the whip on your sister.She loves the cock.

crack the whip by doyle November 21, 2003

fair crack of the whip 

Australian colonial term meaning to give someone a fair chance or cut them a break.

Probably derived from when the original convict Australians were whipped with a "cat o nine tail" for any old indiscretion whether deserved or not...

Woman: Get out of my bed!
Man: Why?
Woman: Because you are not performing to my expectations softy!
Man: Fair crack of the whip! I'm drunk! ....Mumble mumble... Crazy Sheila.....

fair crack of the whip by Pertinentsnsuch February 14, 2014

Crack the Yellow Whip 

When you gotta whip out that pee stream

"Todd had to go to the bathroom and go crack the yellow whip."

Crack the Yellow Whip by NolDan August 31, 2017