Ancient fabulist (5)
I believe the answer is:
aesop
'ancient fabulist' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for aesop that I've seen before include "Ancient Greek author of moral tales" , "So ape the writer of fables" , "satirical writer" , "A pose by Greek writer of fables" , "Classic fable writer" .)