Increase waste when former partner is home (9)

I believe the answer is:

increment

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'increase' is the definition.
('increment' can be a synonym of 'increase')

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(Other definitions for increment that I've seen before include "Increase (one of a series)" , "additional pay" , "Addition to wages etc" , "Amount by which something increases" , "Small addition to salary etc" .)

I've seen this clue in The Independent.

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