Wave to ship for a ride (6,7)
I believe the answer is:
roller coaster
'a ride' is the definition.
(roller coaster is a kind of ride)
'wave to ship' is the wordplay.
'wave' becomes 'roller' (roller is a kind of wave).
'to ship' becomes 'coaster' (coaster is a type of ship).
'roller'+'coaster'='ROLLER-COASTER'
'for' is the link.
(Other definitions for roller coaster that I've seen before include "Switchback" , "Exciting ride" , "Fairground ride" , "Series of emotional swings" , "Big dipper" .)