Art of oratory (8)
I believe the answer is:
rhetoric
'art of oratory' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for rhetoric that I've seen before include "Torchier kind of eloquent talk" , "Torchier with language of orator" , "Vague talk and empty promises" , "Empty words?" , "Language used for its dramatic sound" .)