Make bet her partner's late (7)

I believe the answer is:

dowager

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'her partner's late' is the definition.
I can't tell whether this defines the answer.

'make bet' is the wordplay.
'make' becomes 'do' (do can mean to make or prepare).
'bet' becomes 'wager' (synonyms).
'do'+'wager'='DOWAGER'

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(Other definitions for dowager that I've seen before include "Wealthy old woman" , "Important widow" , "Wordage (anag.)" , "Rich old girl" , "One of 16 [OLD GIRLS]" .)

I've seen this clue in The Sun.

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