One who doesn’t do something that would be funny or cool. Lame really. Party pooper. Could do something real fun like put on a Dino mask but doesn’t do it.
Noun. Most commonly used as a term of derision when an otherwise generally intelligent person does something stupid. However, the term is perfectly acceptable for use to describe a generally stupid person who does something stupid.
Don't look at me nutnard, you're the dealer as you could plainly see by the 'Dealer' chip right in front of you.