Dashed odds on journalist (4)
I believe the answer is:
sped
'dashed' is the definition.
(I've seen this before)
'odds on journalist' is the wordplay.
'odds' becomes 'sp' (betting abbreviation for starting price).
'on' says to put letters next to each other.
'journalist' becomes 'ed' (short for editor).
'sp'+'ed'='SPED'
(Other definitions for sped that I've seen before include "Went fast" , "Moved quickly" , "Made haste" , "Rushed" , "Moved fast" .)