nobesity 

Pretty much the opposite of obesity. Nobesity is the inablity to gain weight, no matter how much the individual eats and/or works out. Sometimes, weight loss may occur.

Tom: Hey, man, how much do you weigh?

John: 125 pounds! (56.7 kilograms)

Tom: That's weird, weren't you 135 pounds (61.2kg) last week?

John: Yeah man, I think it's nobesity.

nobesity by TheRealSquanto February 5, 2014

Noobesity

A condition characterized by the excessive oozing of Stupid from the mouth.

It's not my fault, I was born with noobesity!

Noobesity by Street Dentist November 30, 2006