One who guides or directs a course of action for others, A television program produced as a prototype of a series being considered for adoption by a network, (A?ronautics) One who flies, or is qualified to fly, an airplane, balloon, or other flying machine, transitive verb_ Figuratively_ To guide, as through dangers or difficulties, To direct the course of, as of a ship, where navigation is dangerous, To serve as the pilot of (a plane, for example), adjective_ Serving as a tentative model for future experiment or development, Serving or leading as guide