Person or persons of low intelligence often unwittingly making a fool of themselves in front of their peers. Usually hold themselves in a high regard and have a large ego.
In Chicago, a Goofymark is an absolute clown; a punk; a hoestud; ; a clown; a lame; a goof troop. This is worse than being called a bitch, and warrants an immediate invitation to a fist fight.
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.