- The definition of coz is cousin or friend in U.S. slang.
An example of coz is a name you call a close male friend.
- (informal) cousin (usually as a term of address).
- "Content thee, gentle coz, let him alone" Romeo & Juliet Act I Scene 5
- (informal) because
ConjunctionSee also: coz
- (informal) Alternative form of 'cause.