Glaring may draw attention to diatribe (8)
I believe the answer is:
flagrant
'glaring' is the definition.
(I know that glaring can be written as flagrant)
'draw attention to diatribe' is the wordplay.
'draw attention to' becomes 'flag' (as in to flag or mark something).
'diatribe' becomes 'rant' (I've seen this in other clues).
'flag'+'rant'='FLAGRANT'
'may' acts as a link.
(Other definitions for flagrant that I've seen before include "Shocking" , "Crying" , "notorious" , "Openly outrageous" , "Conspicuous, blatant" .)