Definitions by Lewberto
mag
In England especially, a mag is an exceptionally short penis. The word derives from the word maggot which is the name of a wormlike insect larvae - the connection being that maggots are rather small. The word is used as an insult towards someone who is known or suspected to have a small penis. If the former is the case, then the one with the mag can duly call the insulter a pervert. Usually the accusation is false, and is believed by those who are insecure about the length of their own penis and who feel better about themselves by mocking others.