Mega thicc Posted in M Best definition Mega thicc MIRA Mira is mega thicc Mega thicc: define #2 megathicc Megathicc refers to a person or object that is gargantuanly thicc. Usually focused on the buttocks of a person. Dude, those jeans make John look megathicc! How satisfied are you with the definition? Looking for Mega thicc meaning? Delighted that you discovered the greatest determine on our web site! Recently this definition was actually observed 99 times.