look up any word, like pussy:
 
1.
The act of trying to hit on someone standing adjacent to you while in a public restroom.

Derived from the definition of caking: the act of flirting.

A pun referring to the the Urinal Cake within the urinal of a male restroom.
"Did you hear that Joe totally picked up some other guy in the bathroom."
"Yup. They were urinal caking for about 2 minutes before they started making out."
by Mistressoftheword March 07, 2010