Small room on street accommodating one musician (7)
I believe the answer is:
cellist
'musician' is the definition.
(cellist is a kind of musician)
'small room on street accommodating one' is the wordplay.
'small room' becomes 'cell' (I've seen this before).
'on street' becomes 'st' (I've seen this in other clues).
'accommodating' indicates putting letters inside.
'one' becomes 'i' (Roman numeral).
'cell'+'st'='cellst'
'cellst' going around 'i' is 'CELLIST'.
(Other definitions for cellist that I've seen before include "Member of orchestra" , "E.g. Casals, du Pre" , "Musician in string section" , "Lloyd Webber?" , "Du Pre or Lloyd Weber" .)