Definitions from Wordnet 2.0

• wheelwork consisting of a connected set of rotating gears by which force is transmitted or motion or torque is changed; "the fool got his tie caught in the geartrain"
• public transport provided by a line of railway cars coupled together and drawn by a locomotive; "express trains don''t stop at Princeton Junction"
• piece of cloth forming the long back section of a gown that is drawn along the floor; "the bride''s train was carried by her two young nephews"
• a series of consequences wrought by an event; "it led to a train of disasters"
• a procession (of wagons or mules or camels) traveling together in single file; "we were part of a caravan of almost a thousand camels"; "they joined the wagon train for safety"
• a sequentially ordered set of things or events or ideas in which each successive member is related to the preceding; "a string of islands"; "train of mourners"; "a train of thought"
• exercise in order to prepare for an event or competition; "She is training for the Olympics"
• undergo training or instruction in preparation for a particular role, function, or profession; "She is training to be a teacher"; "He trained as a legal aid"
• create by training and teaching; "The old master is training world-class violinists"; "we develop the leaders for the future"
• teach and supervise (someone); act as a trainer or coach (to), as in sports; "He is training our Olympic team"; "She is coaching the crew"
• aim or direct at; as of blows, weapons, or objects such as photographic equipment; "Please don''t aim at your little brother!"; "He trained his gun on the burglar"; "Don''t train your camera on the women"; "Take a swipe at one''s opponent"
• drag loosely along a surface; allow to sweep the ground; "The toddler was trailing his pants"; "She trained her long scarf behind her"
• travel by rail or train; "They railed from Rome to Venice"; "She trained to Hamburg"
• prepare (someone) for a future role or function; "He is grooming his son to become his successor"; "The prince was prepared to become King one day"; "They trained him to be a warrior"
• train to be discriminative in taste or judgment; "Cultivate your musical taste"; "Train your tastebuds"; "She is well schooled in poetry"
• train to grow in a certain way by tying and pruning it; "train the vine"
• train by instruction and practice; especially to teach self-control; "Parents must discipline their children"; "Is this dog trained?"

Definitions from Wiktionary

• public transport provided by a line of railway cars coupled together and drawn by a locomotive; "express trains don't stop at Princeton Junction" ,
• a sequentially ordered set of things or events or ideas in which each successive member is related to the preceding; "a string of islands"; "train of mourners"; "a train of thought" ,
• a procession (of wagons or mules or camels) traveling together in single file; "we were part of a caravan of almost a thousand camels"; "they joined the wagon train for safety" ,
• a series of consequences wrought by an event; "it led to a train of disasters" ,
• piece of cloth forming the long back section of a gown that is drawn along the floor; "the bride's train was carried by her two young nephews" ,
• wheelwork consisting of a connected set of rotating gears by which force is transmitted or motion or torque is changed; "the fool got his tie caught in the geartrain"

A train is a series of cars on a railway. It is like a special bus that can only drive on rails. It can be used for transporting people and goods. A place where a train stops, to let people get on and off, is called a railway station. The locomotive pulls the cars along the track. Trains are used to carry people, as well as cargo, such as fuel, imported/exported goods, and so on.

Freight cars carry goods from one place to another on special cars called freight cars.

Passenger cars are specially made so people can ride them from station to station. There are very few passenger cars in the United States, but a lot more in Europe.

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