A hero, hard yet shaky (5)
I believe the answer is:
rocky
'shaky' is the definition.
(synonyms)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for rocky that I've seen before include "Characterised by large stones" , "Craggy; difficult" , "fighter making many comebacks" , "Uneven" , "'-' Marciano, US boxer" .)