Maybe returning to the flat (5)

I believe the answer is:

level

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

I can't explain the rest of the clue.

(Other definitions for level that I've seen before include "Neck and neck" , "status" , "Device ot establish a flat surface" , "Palindromically smooth" , "Floor; horizontal" .)

I've seen this clue in the Evening Standard.

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