A group of people who constantly bag each others mums. As if they have nothing better to do.
Guy 1: ya mamas so fat, that went she went to the airport she got arrested for carrying 100 pounds of crack

Guy 2: ya mumas so fat she had to get baptised at sea world

Guy 3: ya mumas so dumb she tripped over a cordless phone

Guy 1: Wow. This a a real ya mumathon

Guy 1&2: Yeah
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