Crossword Genius

Other than bums may be contracted in this (2,6)

Ross

I believe the answer is:

no trumps

'may be contracted in this' is the definition.
(term in contract bridge)

'other than bums' is the wordplay.
'other than' becomes 'not'.
'bums' becomes 'rumps' ('rump' can be a synonym of 'bum').
'not'+'rumps'='NO-TRUMPS'

(Other definitions for no trumps that I've seen before include "Call" , "Sort of contract" .)

I've seen this clue in The Guardian.
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