Ist is defined as involved in a particularly field or having a certain interest or belief.
(suffix)An example of ist used as a suffix is in the word druggist, a person with an interest in drugs and medications.
See -ist in Webster's New World College Dictionary
Origin: ME -iste < OFr < L -ista < Gr -istēs < verbs ending in -izein
See -ist in American Heritage Dictionary 4
Origin:
Origin: Middle English -iste
Origin: , from Old French
Origin: , from Latin -istēs, -ista
Origin: , from Greek -istēs, agent n. suff
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