n. A hinged board or closure at the rear of a vehicle, such as a pick-up truck, that can be lowered during loading and unloading. Also called tailboard.n. One of the pair of gates downstream in a canal lock.v. To drive so closely behind (another vehicle) that one cannot stop or swerve with ease in an emergency.v. Slang To follow closely behind (another person), as in gaining access to an area requiring the use of an electronic identification card.verb-intransitive. To follow another vehicle too closely.verb-intransitive. To participate in a picnic that is served from the tailgate of a vehicle, as before a sports event.