Many (particularly sci-fi) shows or books invent words to replace real words, for example 'frak' in Battlestar Galactica replaces the 'F' word to get through censorship.
Is there a word to describe a word like 'frak', a word used in place of another? Not necessarily always replacing a curse word, I'm only using this as an example. My first thoughts were proxy or intimation but that's not quite right.