-ist
/ɪst/suffix
Forming personal nouns and some related adjectives:
1Denoting an adherent of a system of beliefs, principles, etc. expressed by nouns ending in -ism: hedonist Calvinist See -ism (sense 2).
1.1Denoting a person who subscribes to a prejudice or practises discrimination: sexist
2Denoting a member of a profession or business activity: dentist dramatist florist
2.1Denoting a person who uses a thing: flautist motorist
2.2Denoting a person who does something expressed by a verb ending in -ize: plagiarist
Origin
From Old French -iste, Latin -ista, from Greek -istēs.