Detective rejects no bribe (5)

I believe the answer is:

snoop

I'm a little stuck... Click here to teach me more about this clue!

'detective' is the definition.
(I've seen this in another clue)

I don't understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for snoop that I've seen before include "Investigate; pry" , "Furtively look around" , "Stick one's nose in" , "-- Dogg, US rapper; spy" , "Furtively investigate" .)

I've seen this clue in The Irish Times.

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