<p><strong>Noun</strong></p><ul><li>Railroads: a self-propelled, connected group of rolling stock.</li><li>a line or procession of persons, vehicles, animals, etc., traveling together.</li><li>Military: an aggregation of vehicles, animals, and personnel accompanying an army to carry supplies, baggage, ammunition, etc.</li><li>Synonyms: convoy.</li><li>a series or row of objects or parts.</li><li>Machinery: a connected set of three or more rotating elements, usually gears, through which force is transmitted, or motion or torque changed.</li><li>order, especially proper order: Matters were in good train.</li><li>Synonyms: arrangement, array.</li><li>something that is drawn along; a trailing part.</li><li>an elongated part of a skirt or robe trailing behind on the ground.</li><li>a trail or stream of something from a moving object.</li><li>a line or succession of persons or things following one after the other.</li><li>Synonyms: column, file.</li><li>a body of followers or attendants; retinue.</li><li>a series of proceedings, events, ideas, etc.</li><li>the series of results or circumstances following or proceeding from an event, action, etc.; aftermath: Disease came in the train of war.</li><li>a succession of connected ideas; a course of reasoning: to lose one's train of thought.</li><li>Astronomy: the trace of light created by a meteor falling through the earth's atmosphere; the tail of a comet.</li><li>a line of combustible material, as gunpowder, for leading fire to an explosive charge.</li><li>Physics: a succession of wave fronts, oscillations, or the like.</li></ul><p><strong>Verb (used with object)</strong></p><ul><li>to develop or form the habits, thoughts, or behavior of (a child or other person) by discipline and instruction: to train an unruly boy.</li><li>to make proficient by instruction and practice, as in some art, profession, or work: to train soldiers.</li><li>Synonyms: school, practice, drill, exercise.</li><li>to make (a person) fit by proper exercise, diet, practice, etc., as for an athletic performance.</li><li>to discipline and instruct (an animal), as in the performance of tasks or tricks.</li><li>to treat or manipulate so as to bring into some desired form, position, direction, etc.: to train one's hair to stay down.</li><li>Horticulture: to bring (a plant, branch, etc.) into a particular shape or position, by bending, pruning, or the like.</li><li>to bring to bear on some object; point, aim, or direct, as a firearm, camera, telescope, or eye.</li><li>Archaic: to entice; allure.</li></ul><p><strong>Verb (used without object)</strong></p><ul><li>to give the discipline and instruction, drill, practice, etc., designed to impart proficiency or efficiency.</li><li>to undergo discipline and instruction, drill, etc.</li><li>to get oneself into condition for an athletic performance through exercise, diet, practice, etc.</li><li>to travel or go by train: to train to New York.</li></ul>