pilot

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun One who operates or is licensed to operate an aircraft in flight.
• noun One who, though not belonging to a ship's company, is licensed to conduct a ship into and out of port or through dangerous waters.
• noun The helmsman of a ship.
• noun One who guides or directs a course of action for others.
• noun The part of a tool, device, or machine that leads or guides the whole.
• noun A pilot light, as in a stove.
• noun A television program produced as a prototype of a series being considered for adoption by a network.
• transitive verb To serve as the pilot of (a plane, for example).
• transitive verb To steer or control the course of: synonym: guide.
• adjective Serving as a tentative model for future experiment or development.
• adjective Serving or leading as guide.

from The Century Dictionary.

• To steer; direct the course of, especially through an intricate or perilous passage; guide through dangers or difficulties.
• noun In machinery, a smaller element acting in advance of another or principal element of the same sort, and causing the latter to come into play when desired.
• noun The steersman of a ship; that one of a ship's crew who has charge of the helm and the ship's course; specifically, one who works a ship into and out of harbor, or through a channel or passage.
• noun A guide; a director of the course of others; one who has the conduct of any affair requiring knowledge and judgment.
• noun Same as cow-catcher. See cut under passenger-engine.
• noun A book of sailing-directions.
• noun Pilot-cloth.
• noun The pilot-fish.
• noun The black-bellied plover, Squatarola helvetica.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb To direct the course of, as of a ship, where navigation is dangerous.
• transitive verb Figuratively: To guide, as through dangers or difficulties.
• transitive verb (Aëronautics) To fly, or act as pilot of (an aircraft); to operate (an airplane).
• noun (Naut.) One employed to steer a vessel; a helmsman; a steersman.
• noun Specifically, a person duly qualified, and licensed by authority, to conduct vessels into and out of a port, or in certain waters, for a fixed rate of fees.
• noun Figuratively: A guide; a director of another through a difficult or unknown course.
• noun An instrument for detecting the compass error.
• noun U.S. The cowcatcher of a locomotive.
• noun (Aëronautics) One who flies, or is qualified to fly, an airplane, balloon, or other flying machine.
• noun (Mach.) A short plug at the end of a counterbore to guide the tool. Pilots are sometimes made interchangeable.
• noun (Mining) The heading or excavation of relatively small dimensions, first made in the driving of a larger tunnel.
• noun (Television) a filmed or taped episode of a proposed television series, produced as an example of the series. It may be shown only to those television broadcast executives who may decide whether to buy the rights to the series, or aired to test viewer reaction or to interest sponsors. Also called pilot film or pilot tape.
• noun a small balloon sent up in advance of a large one, to show the direction and force of the wind.
• noun (Zoöl.), [Local, U.S.] The black-bellied plover.
• noun a strong, fast-sailing boat used to carry and receive pilots as they board and leave vessels.
• noun ship biscuit.
• noun a coarse, stout kind of cloth for overcoats.
• noun a locomotive going in advance of a train to make sure that the way is clear.
• noun (Zoöl) The rudder fish (Seriola zonata).
• noun a flag or signal hoisted by a vessel for a pilot.
• noun a pea jacket.
• noun (Bridge Building) a conical nut applied temporarily to the threaded end of a pin, to protect the thread and guide the pin when it is driven into a hole.
• noun (Zoöl.) The pine snake.
• noun (Zoöl.) Same as Blackfish, 1.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A person who steers a ship, a helmsman.
• noun A person who knows well the depths and currents of a harbor or coastal area, who is hired by a vessel to help navigate the harbor or coast.
• noun this sense?) (road transport) A vehicle to warn other road users of the presence of an oversize vehicle/combination.
• noun A guide or escort through an unknown or dangerous area.
• noun Something serving as a test or trial.