Popular prophesy with a Latin opening (9)
I believe the answer is:
inaugural
'opening' is the definition.
(similar in meaning)
'popular prophesy with a latin' is the wordplay.
'popular' becomes 'in' ('in' can mean trendy).
'prophesy' becomes 'augur' (I've seen this before).
'with' says to put letters next to each other.
'latin' becomes 'l'.
'in'+'augur'+'a'+'l'='INAUGURAL'
(Other definitions for inaugural that I've seen before include "Relating to start of job or course" , "President's address" , "Of a ceremony officially marking the beginning of something" , "Introductory" , "Marking the beginning of, eg, an institution" .)