A sore loser is someone who bitches and moans after losing some sort of game or contest. A sore loser is someone who cannot take defeat with dignity, someone who, at the end, scatters all the checkers and shouts, "This game is dumb anyway!"

Many right-aligned Americans believed that Al Gore was a sore loser because he refused to concede the last presidential election for some time. Many left-aligned Americans believed that Richard Nixon was a sore loser through much of his political career, always under the impression that something rightfully his had been stolen from him.