Increase, breaking the hinge (8)

I believe the answer is:

heighten

'increase' is the definition.
(heightening is a kind of increasing)

'breaking the hinge' is the wordplay.
'breaking' indicates anagramming the letters.
'the'+'hinge'='thehinge'
'thehinge' with letters rearranged gives 'HEIGHTEN'.

(Other definitions for heighten that I've seen before include "effect some improvement" , "Elevate - intensify" , "Increase in amount of degree" , "Intensify; make taller" , "Make more intense - elevate?" .)

I've seen this clue in the Evening Standard.

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