Instrument is returned to sailor (5)
I believe the answer is:
sitar
'instrument' is the definition.
(sitar is a type of musical instrument)
'is returned to sailor' is the wordplay.
'returned' says the letters should be written in reverse.
'to sailor' becomes 'tar' (term for a sailor).
'is' in reverse letter order is 'si'.
'si'+'tar'='SITAR'
(Other definitions for sitar that I've seen before include "Guitar-like instrument" , "Hindu string instrument" , "Astir with Indian long-necked lute" , "music producer" , "music-maker" .)