The activist language merry-go-round refers to the way terms about minorities fall in and out of favor and common use. When used metaphorically, a merry-go-round is a continuous cycle of events or activities. The word is most commonly used when the cycle is pointless or unproductive.
Transgender academic and writer Julia Serrano first used the term activist language merry-go-round. She believes stigma drives the activist language merry-go-round. New words are created to protect minorities from stigma. However, as minorities remain stigmatized, any word concerning them eventually becomes tainted, too. It is then replaced with a new word, beginning the cycle all over again.
The term can be used interchangeably with euphemism treadmill. However, words we have euphemisms for don’t necessarily concern minorities.