A fork of Rural Dictionary
Finning is the act of sticking a finn shaped object into the female genitalia and then wiggling or flopping around like a finn normally would. This can be accomplished by making your hand into the shape of a finn, or using an actual finn of some type, which is much more rare. Either way, this is a legendary move that will surely change the girl's life forever.
"How did it go with that girl last night?" "Awesome. I ended up Finning her. Her life will never be the same." "Legendary."