Attire that's worn by bishop? (7)
I believe the answer is:
'attire that's worn by bishop?' is the definition.
I can't tell whether this defines the answer.
'attire that's worn by bishop?' is the wordplay.
'that's worn' indicates anagramming the letters (worn can mean damaged).
'by' is a charade indicator (letters next to each other).
'bishop?' becomes 'b' (chess abbreviation).
'attire' is an anagram of 'iretta'.
'iretta' put after 'b' is 'BIRETTA'.
(Other definitions for biretta that I've seen before include "Battier (anag.)" , "Square cap worn by Roman Catholic clergy" , "ecclesiastical headgear" , "Cardinal's red cap" , "religious headwear" .)