Someone who fastidiously insists on something (8)

I believe the answer is:

stickler

(Other definitions for stickler that I've seen before include "Person who insists on something, say punctuality - sounds adhesive" , "One insistent on things being just so" , "Someone who insists on something" , "Particular type" , "Disciplinarian, martinet" .)

I've seen this clue in The Irish Times.

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