Vaulting game (8)
I believe the answer is:
leapfrog
'vaulting game' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for leapfrog that I've seen before include "Vaulting game" , "Overtake in position" , "Child's game of jumping over competitors" , "Advance by jumping over the opposition" , "Advance by jumps" .)