Sign for esoteric sectarian (10)

I believe the answer is:

prognostic

'sign' is the definition.
(prognostic is a kind of sign)

'for esoteric sectarian' is the wordplay.
'for' becomes 'pro' (I've seen this before).
'esoteric sectarian' becomes 'gnostic'.
'pro'+'gnostic'='PROGNOSTIC'

(Other definitions for prognostic that I've seen before include "Making prediction" , "Sign" .)

I've seen this clue in The Times.

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