No, it isn't all a new ceremony (12)
I believe the answer is:
installation
'ceremony' is the definition.
(I know that installation is a type of ceremony)
'no it isn't all a new' is the wordplay.
'new' is an anagram indicator.
'no'+'it'+'isnt'+'all'+'a'='noitisntalla'
'noitisntalla' anagrammed gives 'INSTALLATION'.
(Other definitions for installation that I've seen before include "The making of equipment ready for use" , "Exhibit constructed in a gallery" , "Art exhibit in gallery" , "Large gallery artwork" , "military base" .)