Doctor and old lady get on around ship (7)
I believe the answer is:
massage
'doctor' is the definition.
(both can mean to manipulate figures or information)
'old lady get on around ship' is the wordplay.
'old lady' becomes 'ma' (both can mean mother).
'get on' becomes 'age' (synonyms).
'around' is an insertion indicator.
'ship' becomes 'SS' (prefix in ship names eg SS Great Britain).
'ma'+'age'='maage'
'maage' going around 'ss' is 'MASSAGE'.
'and' acts as a link.
(Other definitions for massage that I've seen before include "Manipulation of the muscles" , "Manipulate the muscles" , "Relaxing treatment" , "See 10" , "therapeutic treatment" .)