n. Used to describe someone who is retarded, moronic, stupid,
inept, etc.
Derived from the disorder
Trisomy 21, which is the cause for down syndrome. A handy phrase to use in public when you want to call something retarded, but the non-politically correct nature of the word doesn't
allow you to do so.
Person 1: "Did you hear that
Robbie failed all of his
classes?"
Person 2: "Wow, what a fucking 321"
Person 1: "Such a 321... after I told him I failed one, he was like 'That's NOTHING, I failed ALL of mine.'"