racefart
To call someone a racist for personal gain, such as to silence another, to close down an argument and thinking you have won it, or to undermine someone in the eyes of others. The term first became popular in the West Midlands area of England as a way of 'calling out' a person for causing offence by accusing another of being racist.
Initially was simple, such as "You just racefarted". Over time it has become more imaginative, such as "X dropped a wicked racefart. The stink lingered long after he left the room".