Motor (6)
'motor' is the definition.
(I know that motor can be written as engine)
This is the entire clue.
(Other definitions for engine that I've seen before include "search, maybe" , "Power unit" , "turn of mind once" , "Motor" , "Mechanical device as source of power, a driver" .)
'motor' is the definition.
(informal term for car)
This is all the clue.
(Other definitions for car that I've seen before include "estate, perhaps" , "One for the road?" , "Road vehicle; rail coach" , "Wheeled vehicle" , "Passenger vehicle" .)
'motor' is the definition.
(an inboard is a boat's engine)
This is all the clue.
(Other definitions for inboard that I've seen before include "(Motor) within ship" , "description of boat's engine" , "Seated inside executive jet" , "Within a ship or plane" , "Within a ship's hull" .)