IPA: //ˌsɛpəˈreɪʃənɪst//
KK: /ˌsɛpəˈreɪʃənɪst/
A person who supports the separation of a particular group from a larger body, often for political, cultural, or religious reasons.
The separationist movement aimed to create an independent state for the minority group.
Separationist → It is formed from "separation" (from Latin "separatio", meaning a setting apart) and the suffix "-ist" (meaning a person who practices or advocates). A separationist is a person who advocates for the separation of a group from a larger entity.
Think of someone who advocates for 'setting apart' ('separatio') — that's what a separationist does.