Definitions by HotCarl

greenlighting 

A practice whereby any male or female will wear a green polo (or otherwise collared shirt) with the collar up in order to signal readiness for promiscuous anonymous sex. Anyone seeing this signal may pop the collar down of the person wearing the shirt and go on to have sex.

I was greenlighting yesterday when this foxy chick collared me.

greenlighting by HotCarl July 19, 2005