Month with evangelical Tory on vacation? That's different! (7)
I believe the answer is:
novelty
'that's different' is the definition.
(something different is a novelty)
'month with evangelical tory on vacation?' is the wordplay.
'month' becomes 'nov' (Nov is an example).
'with evangelical' becomes 'el' (I can't justify this - if you can you should believe this answer much more).
'on vacation?' says to hollow out the word (remove centre letters) (I've seen 'on vacation' mean this).
'tory' with its centre removed is 'ty'.
'nov'+'el'+'ty'='NOVELTY'
(Other definitions for novelty that I've seen before include "Small, cheap ornament" , "Something new and strange" , "Middle-Eastern language" , "Something new and unusual" , "Innovation" .)