Began meal, entertaining ace journalist (8)
I believe the answer is:
launched
'began' is the definition.
(launching is a kind of beginning)
'meal entertaining ace journalist' is the wordplay.
'meal' becomes 'lunch' (lunch is a kind of meal).
'entertaining' is an insertion indicator (inviting in, as for dinner).
'ace' becomes 'a' (abbreviation).
'journalist' becomes 'ed' (short for editor).
'lunch' enclosing 'a' is 'launch'.
'launch'+'ed'='LAUNCHED'
(Other definitions for launched that I've seen before include "Sent into space" , "Sent on course as uncle had" , "Set a ship in motion" , "Sent a newly-built boat into the water" , "Propelled" .)