A man with an abundance of joy in his pants. Men named Matt are often defined as such. Favorite positions are cowgirl and reverse cowgirl. Let the women ride until they're warm through before they hop off the saddle.
Did you see Matt the other day? Yeah he's a horny cowboy!! That girl would not get off his saddle.
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"