Solicitor welcoming knight back, visitor (7)
I believe the answer is:
tourist
'visitor' is the definition.
(I've seen this before)
'solicitor welcoming knight back' is the wordplay.
'solicitor' becomes 'tout' (I've seen this before).
'welcoming' means one lot of letters goes inside another (in sense of 'inviting in').
'knight' becomes 'sir' (I've seen this before**).
'back' is a reversal indicator.
'sir' in reverse letter order is 'ris'.
'tout' placed around 'ris' is 'TOURIST'.
(Other definitions for tourist that I've seen before include "One travels for pleasure" , "Tripper, sightseer" , "Cheap travel class" , "someone on holiday" , "Sightseeing holidaymaker" .)