Could be but a trite quality (9)
I believe the answer is:
attribute
'quality' is the definition.
(I know that quality can be written as attribute)
'could be but a trite' is the wordplay.
'could be' indicates anagramming the letters.
'but'+'a'+'trite'='butatrite'
'butatrite' with letters rearranged gives 'ATTRIBUTE'.
(Other definitions for attribute that I've seen before include "Point" , "Impute - quality" , "Assign" , "Quality characteristic of person or thing" , "Ascribe, impute" .)