English word multicultist comes from English multicultural (Relating or pertaining to several different cultures.), English cultist (A member of a cult.)

Detailed word origin of multicultist

Dictionary entry	Language	Definition
multicultural	English (eng)	Relating or pertaining to several different cultures.
cultist	English (eng)	A member of a cult.
multicultist	English (eng)	(often, pejorative) One who is in favor of multiculturalism.