Joe mama is a joke usually performed my middle schoolers, the joke will most likely start of with a conversation with two people, a random person will come up an ask you the question "whose Joe". Most likely the people in the conversation will yell "JOE MAMA"
Joe mama, is another way of saying your mother. But only use this when the mother's name is any spelling of meghan pronounce ( meg-an )
Person one: Hey is Joe mama home?
Person two : Huh?
Person one : your mom's name is meghan right?
Person two : yeah
Person one : so is Joe mama home?
Person two: oh yeah I guess....