Brazier exploded -- that's unusual (7)
I believe the answer is:
bizarre
'unusual' is the definition.
(thesaurus)
'brazier exploded' is the wordplay.
'exploded' indicates an anagram.
'brazier' with letters rearranged gives 'BIZARRE'.
'that's' is the link.
(Other definitions for bizarre that I've seen before include "Really weird" , "Funny" , "Freakish" , "Way-out" , "Weird and wonderful" .)