One who makes a very idiotic action, generally one that could've been avoided with the use of common sense or basic brain functioning.

When you eat dirt for the first time and leave your family to build a shack in the woods

Some one with a dumbfound look on their face. A stupid face.

a very stupid person who wouldn't understand just being called stupid; commonly used for the stupidest people you will ever know who would try forever to figure out what the deviation between stupid and stupid face is....by the way, there is NONE.

a playful word to describe someone who has offended you in a kidding kind of way

A trait held by humans, giving them a face resembling stupid in its physical form.

A person that is stupid and has a face (example: Monique)
A person that has a stupidface
(example: Monique)