Actor's first to go over contract (7)
I believe the answer is:
abridge
'contract' is the definition.
(synonyms)
'actor's first to go over' is the wordplay.
'actor's first' becomes 'a' (1st letter of 'actor').
'to go over' becomes 'bridge'.
'a'+'bridge'='ABRIDGE'
(Other definitions for abridge that I've seen before include "Condense, summarise" , "prune?" , "Remove sections" , "Make shorter in brigade" , "Cut short" .)