Reverse ends (5)
I believe the answer is:
tails
I believe this is a double definition.
'reverse' is the first definition.
(thesaurus)
'ends' is the second definition.
(tail is a kind of end)
(Other definitions for tails that I've seen before include "Morning coat" , "the back of bears - bulls too" , "Ends" , "Evening dress; coin toss call" , "as opposed to heads" .)