Clothes I treat badly (6)
I believe the answer is:
attire
'clothes' is the definition.
(attire is clothing)
'i treat badly' is the wordplay.
'badly' indicates anagramming the letters (letters in the wrong order).
'i'+'treat'='itreat'
'itreat' with letters rearranged gives 'ATTIRE'.
(Other definitions for attire that I've seen before include "12" , "Clothes worn" , "(To) dress; fine clothes" , "Clothing - tear it (anag)" , "Wear" .)