Mobility aid for city professorship (9)

I believe the answer is:

bathchair

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'mobility aid' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'city professorship' is the wordplay.
'city' becomes 'bath' (English city).
'professorship' becomes 'chair' (synonyms).
'bath'+'chair'='BATHCHAIR'

'for' acts as a link.

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I've seen this clue in The Daily Express.

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