Native American's somewhat faddish opinions (4)
I believe the answer is:
hopi
'native american's' is the definition.
(I've seen this in another clue)
'somewhat faddish opinions' is the wordplay.
'somewhat' indicates the answer is hidden within the clue.
'HOPI' is hidden in the letters of 'faddish opinions'.
(Other definitions for hopi that I've seen before include "Member of a Pueblo Indian people of northeastern Arizona" , "Pueblo tribe member" , "Arizonan Pueblo Indian" , "North American Indian people" , "Native Americans" .)