Comb for sale — two pounds off (4)

I believe the answer is:

toss

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'comb' is the definition.
(thesaurus)

I can't explain the remainder of the clue.

(Other definitions for toss that I've seen before include "Flip up into the air - coin or salad" , "Leave decision to chance" , "Flip in the air, sald or coin" , "cast" , "Ditch" .)

I've seen this clue in The Times and The Sunday Times.

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