Where on reflection you may be speedily caught (5,4)

I believe the answer is:

radar trap

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'where on reflection you may be speedily caught' is the definition.
The definition suggests a singular noun which matches the answer.

This is the entire clue.

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(Other definitions for radar trap that I've seen before include "Changed to be more spiritual" , "a catch, if one's too quick!" , "enforcement mechanism" .)

I've seen this clue in The Times.

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