Art Deco to bizarre degree (9)
I believe the answer is:
doctorate
'degree' is the definition.
(doctorate is a kind of degree)
'art deco to bizarre' is the wordplay.
'bizarre' is an anagram indicator.
'art'+'deco'+'to'='artdecoto'
'artdecoto' is an anagram of 'DOCTORATE'.
(Other definitions for doctorate that I've seen before include "Higher degree" , "Highest degree in university" , "High degree" , "Postgraduate degree" , "Academic qualification" .)