Go back to bed (6)
I believe the answer is:
retire
I believe this clue is a double definition.
'go back' is the first definition.
(thesaurus)
'bed' is the second definition.
(I know that bed can be written as retire)
'to' acts as a link.
(Other definitions for retire that I've seen before include "Step down" , "Leave work; go back" , "Leave job permanently (6)" , "Pull back" , "Withdraw from active participation" .)