Hero otherwise has origin (4)
I believe the answer is:
root
'origin' is the definition.
(I know that origin can be written as root)
'hero otherwise has' is the wordplay.
'has' indicates the answer is hidden within the clue.
'ROOT' is hidden in the letters of 'hero otherwise'.
(Other definitions for root that I've seen before include "Solution of equation" , "Basic source or origin" , "top of tree? Hardly!" , "Underground growth" , "could be square" .)