Eclipse London-bound coach (7)
I believe the answer is:
upstage
'eclipse' is the definition.
(I've seen this before)
'london-bound coach' is the wordplay.
'london-bound' becomes 'up' ('up' can mean at an important place, esp. London).
'coach' becomes 'stage' (stagecoach).
'up'+'stage'='UPSTAGE'
(Other definitions for upstage that I've seen before include "Try to attract attention" , "Outshine" , "Divert attention from someone towards yourself" , "Furthest from the audience (in theatre)" , "moved away from the audience" .)