Crossword Genius

A habit makes us grow old (5)

Ross

I believe the answer is:

usage

'a habit' is the definition.
(I've seen this before)

'us grow old' is the wordplay.
'grow old' becomes 'age' (synonyms).
'us'+'age'='USAGE'

'makes' acts as a link.

(Other definitions for usage that I've seen before include "Habitual custom" , "Way of treating" , "Terminology - custom" , "Custom; practice" , "Accepted or habitual practice" .)

I've seen this clue in The Globe and Mail.
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