-ister-istresuffix

suffix representing. Old French -istre, a by-form of -iste, -ist suffix, considered by French etymologists to have arisen through false analogy with words like ministre. Found in Old French at an early date, as in evangelistre (12–13th centuries in Godefroy Compl.), beside evangeliste; so choristre, decretistre, legistre, listre or litre (reader), etc. From Old French, these forms passed into English, where they were spelt first -istre, as in alkamystre, decretistre, divinistre, legistre, listre, queristre; afterwards -ister, as in alchimister, chorister, palmister, sophister. In this latter form, the -er was apparently associated with the native suffix -er, which appears as an addition in many nouns denoting office or occupation, derived from or through French, as astrologer, astronomer, geographer, parishioner, practitioner, †musicianer, etc.