Goes to bed (7)
'goes to bed' is the definition.
('retire' can be a synonym of 'go to bed')
This is the entire clue.
(Other definitions for retires that I've seen before include "Gives up work" , "Withdraws" , "Pulls out" , "turns in" , "Goes to bed" .)
'goes to bed' is the definition.
('hit the hay' can be a synonym of 'go to bed')
This is all the clue.