Traditional story or myth (6)
I believe the answer is:
legend
I believe this clue is a double definition.
'traditional story' is the first definition.
(I've seen this before)
'myth' is the second definition.
(I've seen this before)
(Other definitions for legend that I've seen before include "Story about mytical beings" , "extremely famous person?" , "The story of Achilles, say" , "Ancient story" , "explanation" .)