Storyteller's revolutionary main work (5)
I believe the answer is:
aesop
'storyteller's' is the definition.
(Aesop is an example)
'revolutionary main work' is the wordplay.
'revolutionary' says the letters should be written backwards.
'main' becomes 'sea' (synonyms).
'work' becomes 'op' (abbreviation for opus).
'sea' written backwards gives 'aes'.
'aes'+'op'='AESOP'
(Other definitions for aesop that I've seen before include "Greek author of fables (c 620-560 BC)" , "classic author" , "A pose of famed fable teller" , "story teller" , "Greek fabulist (Tortoise and the Hare)" .)