New: a perfume beginning to develop (7)
I believe the answer is:
nascent
'beginning to develop' is the definition.
(nascent means developing or new)
'new a perfume' is the wordplay.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'perfume' becomes 'scent' (synonyms).
'n'+'a'+'scent'='NASCENT'
(Other definitions for nascent that I've seen before include "Starting existence" , "Starting to grow" , "Starting to develop" , "just coming into effect" , "Beginning to develop, embryonic" .)