I relate composition in studio (7)
I believe the answer is:
atelier
'studio' is the definition.
(atelier is a kind of studio)
'i relate composition in' is the wordplay.
'composition' indicates an anagram (letters arranged or composed in a different order).
'in' indicates putting letters inside.
'relate' with letters rearranged gives 'ateler'.
'i' going inside 'ateler' is 'ATELIER'.
(Other definitions for atelier that I've seen before include "I relate to workshop used by artist" , "Artist's workshop, studio" , "Artist's studio (French)" , "room for artist" , "Artist's workroom" .)