Short for Cock Sucker Mother Fucker. Or (as one Co So Mo Fo thought) Cock Sucking Mother Fucker. Either way its somone who sucks cocks cock sucker and fucks mothers motherfucker
by UK_Greg November 19, 2006
When something is done that is macho, undaunted, deliciously retro, heavy metal, punk, redneck, or just plain bad ass, that's so mo!
by pokerclack November 26, 2010