Second contest in film (5)
I believe the answer is:
movie
'film' is the definition.
(I know that film can be written as movie)
'second contest' is the wordplay.
'second' becomes 'mo' (both are short periods of time).
'contest' becomes 'vie' (both can mean to rival or fight).
'mo'+'vie'='MOVIE'
'in' is the link.
(Other definitions for movie that I've seen before include "provide entertainment" , "picture" , "one screened" , "Flick" , "Gladiator for one" .)