An extremely energetic and foolhardy person always looking for attention and adventure by pulling some ridiculous stunt. Usually they will be drunk, but not always. Highly suggestable.
A person who has a lot of "get up and go," but only for retarded, dangerous actions.
Gotard: I'm doing it! Float like a butterfly, sting...uhh, how does the rest of that go?
You: Don't you need a parachute for this?
Gotard: No, just watch. It'll be awesome.
also anyone in a motorized wheelchair, though the public use of this definition would label the user a Go-Tard as well.