A city disposing of land in pieces (7)

I believe the answer is:

asunder

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'in pieces' is the definition.
(asunder means torn apart)

I can't explain the remainder of the clue.

(Other definitions for asunder that I've seen before include "(Split) into pieces" , "going to pieces" , "(Torn) apart" , "bits?" , "(Break) apart" .)

I've seen this clue in The Times.

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