"Meanest shit talk" refers to the most ruthless, aggressive, or cutting remarks someone can make during verbal confrontation or banter. It typically involves insults, criticisms, or mockery aimed at belittling or humiliating the target. This term emphasizes the harshness and severity of the language used in the exchange.
During the heated debate, Sarah unleashed the meanest shit talk I've ever heard, leaving her opponent speechless and defeated.