Song for one person (4)
I believe the answer is:
solo
'song for one person' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for solo that I've seen before include "Go it alone" , "Han - (Star Wars); fly unaccompanied" , "Card game; for one" , "Performed by a single voice or instrument" , "Done by one person" .)