The act of jumping up and bumping chests with someone else.
It is very Gangsta fresh.
Yo' home skillet come here and give me one of a good ol' willi vanilli before you go back home.
HECK YES SON!
The act of jumping up and bumping your chest against another chest in an act of joy or pure thug.
Samson got a strike on Wii golf so he walked up to JimJim and willi vanilli'ed him in pure joy.