Definition of inboard
adverb & adjective
within a ship, aircraft, or vehicle: [as adverb]:the spray was coming inboard now [as adjective]:the uncovered inboard engine toward the center of a ship, aircraft, or vehicle: [as adverb]:move the clew inboard along the boom [as adjective]:the inboard ailerons on the wings were dead
noun
a boat’s engine housed inside its hull. a boat with an inboard engine.