Well-known passage from mystic on I Ching (6)
I believe the answer is:
iconic
'well-known' is the definition.
(both can mean famous)
'passage from mystic on i ching' is the wordplay.
'passage from' indicates a hidden word (a sequence or passage of letters from the clue).
'ICONIC' can be found hidden inside 'mystic on i ching'.
(Other definitions for iconic that I've seen before include "famously representative" , "Stand-out" , "that's like an emoji?" , "Well-known and representative of a particular idea" , "Having the nature of a sacred image" .)