Humiliate the unpretentious (6)
I believe the answer is:
humble
I believe this clue is a double definition.
'humiliate' is the first definition.
(I know that humiliate can be written as humble)
'the unpretentious' is the second definition.
(I've seen this before)
(Other definitions for humble that I've seen before include "Self-effacing" , "Not proud or pretentious" , "Servile" , "beast lacking horns in the Highlands?" , "Conscious of one's shortcomings" .)