Returned funds for circuit (4)

I believe the answer is:

loop

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'circuit' is the definition.
('loop' can be a synonym of 'circuit')

I don't understand the remainder of the clue.

(Other definitions for loop that I've seen before include "I cross myself" , "Noose" , "Shape produced by curve that crosses itself" , "Curve that bends round and crosses itself" , "Circular shape of pool" .)

I've seen this clue in The Times.

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