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light–year

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noun \ˈlīt-ˌyir\

Simple Definition of light–year

  • : a unit of distance equal to the distance that light travels in one year (about 5.88 trillion miles or 9.46 trillion kilometers)

  • light-years —used to say that someone or something is much better or more advanced than others

  • —used to refer to a time that is or seems very far away

Full Definition of light–year

  1. 1 :  a unit of length in astronomy equal to the distance that light travels in one year in a vacuum or about 5.88 trillion miles (9.46 trillion kilometers)

  2. 2 :  an extremely large measure of comparison (as of distance, time, or quality) <seems like light–years ago> <has light–years more talent> <two minutes and yet light–years away from the crowded village — Suzanne Patterson>



LIGHT–YEAR Defined for Kids

light–year

play
noun \ˈlīt-ˌyir\

Definition of light–year

  1. :  a unit of length in astronomy equal to the distance that light travels in one year or about 5.88 trillion miles (9.46 trillion kilometers)




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