Retirement plan? (5)
I believe the answer is:
sleep
'retirement plan?' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sleep that I've seen before include "Snooze" , "''... that knits up the ravell'd sleeve of care'' (Macbeth)" , "Shut-eye" , "Wayne _; former Royal Ballet principal dancer" , "Be dormant" .)