The pipe-player, Tree by name, retired (7)
I believe the answer is:
fireman
'the pipe-player' is the definition.
I can't tell whether this defines the answer.
'tree by name retired' is the wordplay.
'tree' becomes 'fir' (fir is a kind of tree).
'by' means one lot of letters go next to another.
'retired' says the letters should be written in reverse.
'name' written backwards gives 'eman'.
'fir'+'eman'='FIREMAN'
Can you help me to learn more?
(Other definitions for fireman that I've seen before include "Railway driver's assistant" , "Red engine driver" , "Conflagration fighter" , "Chap with a ladder and hose" , "Locomotive stoker" .)