The act of pawing someone with an open palm to the face. A long and exaggerated stroke of the face normally accompanied by either the standard BWEEEAAAAAOOOOOO sound effect or a variety of others.
Jeremy: Godammit don't hit me with the Face Paw I'm trying to read here do that some other time.
It's like face palm, except it's when a Furry does it, generally in character.
"I can't remember my deviantart password to find all my favourite yiff! *face paw*"