Top bid, not bottom (2-5)

I believe the answer is:

no-trump

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(Other definitions for no-trump that I've seen before include "that many left-wing Americans desire?" , "Bid in contract bridge" , "Put morn (anag.); bridge call" , "Highest bid in bridge" , "Bid type that's top" .)

I've seen this clue in The Sunday Times.

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