-ism (/ɪzm/) is an English noun suffix that means "taking side with" or "imitation of", and is often used to describe philosophies, theories, religions, social movements, artistic movements and behaviours
The -ism suffix is related to the suffix -ist, which generally means "a follower of an -ism", e.g. a feminist follows feminism, but can also mean one who does (e.g. scientist).
Teflpedia has some -isms conversation questions.