Moony lout regularly managed to get back (5)
I believe the answer is:
lunar
'moony' is the definition.
(I've seen this in another clue)
'lout regularly managed to get back' is the wordplay.
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
'managed' becomes 'ran' (I've seen this in another clue).
'to get back' says the letters should be written backwards (I've seen 'got back' mean this).
The alternating letters of 'lout' are 'lu'.
'ran' in reverse letter order is 'nar'.
'lu'+'nar'='LUNAR'
(Other definitions for lunar that I've seen before include "Relating to the moon" , "Pertaining to the moon" , "Appertaining to the moon" , "Kind of eclipse" , "of a circling body" .)