Crossword Genius

Alter both reforms in engagement (9)

Ross

I believe the answer is:

betrothal

'engagement' is the definition.
(I know that engagement can be written as betrothal)

'alter both reforms' is the wordplay.
'reforms' indicates anagramming the letters.
'alter'+'both'='alterboth'
'alterboth' anagrammed gives 'BETROTHAL'.

'in' acts as a link.

(Other definitions for betrothal that I've seen before include "Plight" , "Pledge" , "Promise of marriage" , "Commitment" , "Engagement to marry" .)

I've seen this clue in The Daily Express.
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