one who is chubby, but who is also a BAMF. i.e., Peter Griffin and Santa Claus. Can also be someone who annoys you
Shut up chubmuffin, L2lose weight.
by boo-boo GL October 18, 2006
A penis that when erect is wider than it is long.
Danny DeVito is a chubmuffin.
by J~Free February 05, 2011