D defs.my
Entry 1 sense Webster, 1913

-ist

/(ĭsh"ū̇*ĭst)/ · IPA /-ɪst/
01 A noun suffix denoting an agent, or doer, one who practices, a believer in; as, theorist, one who theorizes; socialist, one who holds to so…
  1. 1.
    A noun suffix denoting an agent, or doer, one who practices, a believer in; as, theorist, one who theorizes; socialist, one who holds to socialism; sensualist, one given to sensuality.