Permit unused but not at the beginning (5)

I believe the answer is:

allow

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'permit' is the definition.
(I know that allow is a kind of permit)

I can't explain the remainder of the clue.

(Other definitions for allow that I've seen before include "Permit, let happen" , "Permit or concede" , "brook" , "Acknowledge - concede" , "OK" .)

I've seen this clue in The Guardian.

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