Garda intelligence (3)

I believe the answer is:

cop

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'garda intelligence' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.

This is all the clue.

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(Other definitions for cop that I've seen before include "Member of the police force and an arrest" , "Police officer (informal)" , "Policeman (colloq.)" , "Short policeman" , "Policeman (sl)" .)

I've seen this clue in The Irish Times.

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