Unusual attire bishop’s put on? Yes and no (7)
I believe the answer is:
biretta
'yes and no' is the definition.
I can't tell whether this defines the answer.
'unusual attire bishop's put on?' is the wordplay.
'unusual' indicates an anagram.
'bishop' becomes 'b' (chess abbreviation).
'put on?' is a charade indicator (letters next to each other).
'attire' is an anagram of 'iretta'.
'iretta' put after 'b' is 'BIRETTA'.
(Other definitions for biretta that I've seen before include "Stiff cap worn by Roman Catholic clergy" , "Battier (anag.)" , "Roman Catholic priest's cap" , "ecclesiastical headgear" , "Cardinal's red cap" .)