Insults and criticism for cosmetic (8)
I believe the answer is:
lipstick
'cosmetic' is the definition.
(lipstick is a kind of cosmetic)
'insults and criticism' is the wordplay.
'insults' becomes 'lip' (informal term for insolence).
'and' is a charade indicator (letters next to each other).
'criticism' becomes 'stick' (I've seen this before).
'lip'+'stick'='LIPSTICK'
'for' acts as a link.
(Other definitions for lipstick that I've seen before include "Item of face makeup" , "Type of paint" , "Facial cosmetic" , "Cosmetic used to colour around the mouth" , "Cosmetic item" .)