To smoke weed until you're retarded, as Down's Syndrome is cause by the presence of an extra chromosome.
Chich : We finished a quarter ounce between us last night, man. I think I'm still kinda faced.
Chung : Shit son, you don't watch out you'll smoke yourself a spare chromosome.
Chung : Shit son, you don't watch out you'll smoke yourself a spare chromosome.
by Parhelion February 22, 2009
Get the smoke yourself a spare chromosome mug.