City professorship provides somewhere to sit (4,5)
I believe the answer is:
bath chair
'somewhere to sit' is the definition.
I can't tell whether this defines the answer.
'city professorship' is the wordplay.
'city' becomes 'bath' (English city).
'professorship' becomes 'chair' (synonyms).
'bath'+'chair'='BATH-CHAIR'
'provides' is the link.
Can you help me to learn more?
(Other definitions for bath chair that I've seen before include "occupied by professor in South-West" , "Invalid method of advance" , "Invalid transport" , "post in SW university?" , "Invalid carrier" .)