light-year

noun

\ ˈlīt-ˌyir

How to pronounce light-year (audio)

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Definition of light-year

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 : 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

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More Definitions for light-year

light-year

noun

English Language Learners Definition of light-year

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

—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

See the full definition for light-year in the English Language Learners Dictionary

light-year

noun

\ ˈlīt-ˌyir\

Kids Definition of light-year

: 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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