Correct one side (5)
I believe the answer is:
right
I believe this clue is a double definition.
'correct' is the first definition.
(right can mean correct)
'one side' is the second definition.
(I've seen this before)
(Other definitions for right that I've seen before include "Spot-on" , "Correct; entitlement" , "Fit" , "Correct - claim allowed" , "Properly" .)