noun

1. something that hangs down and drags behind; specif.,
   1. a part of a dress, skirt, etc. that trails
   2. the tail feathers of a bird the train of a peacock
   3. a stream of something trailing behind
2. a group of persons following as attendants in a procession; retinue; suite
3. a group of persons, animals, vehicles, etc. that follow one another in a line; procession; caravan; cortege
4. the persons, vehicles, etc. carrying supplies, ammunition, food, etc. for combat troops
5. a series of events or conditions that follow some happening; aftermath a war bringing famine and disease in its train
6. any connected order or arrangement; series; sequence a train of thought
7. a line of gunpowder, etc. that serves as a fuse for an explosive charge
8. a series of connected mechanical parts for transmitting motion a train of gears
9. a line of connected railroad cars pulled or pushed by a locomotive or locomotives

Etymology: ME traine < OFr trahin < trahiner, to draw on < VL *traginare < L trahere, to pull, draw

transitive verb

1. Rare to trail or drag
2. to guide the growth of (a plant), as by tying, pruning, etc.
3. to subject to certain action, exercises, etc. in order to bring to a desired condition a surgeon's hand trained to be steady
4. to guide or control the mental, moral, etc. development of; bring up; rear
5. to instruct so as to make proficient or qualified to train nurses at a hospital
6. to discipline or condition (animals) to perform tricks or obey commands
7. to prepare or make fit for an athletic contest, etc. as by exercise, diet, etc.
8. to aim (a gun, binoculars, etc.) at something; bring to bear: usually with on
9. Informal to condition (a child, puppy, etc.) to defecate and urinate in the required place

Etymology: ME trainen < OFr trahiner

intransitive verb