light-year

noun
\ ˈlīt-ˌyir How to pronounce light-year (audio) \

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

Synonyms for light-year

Synonyms

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First Known Use of light-year

1867, in the meaning defined at sense 1

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Time Traveler for light-year

Time Traveler

The first known use of light-year was in 1867

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Dictionary Entries Near light-year

lightwood

light-year

light-years ahead

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Cite this Entry

“Light-year.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light-year. Accessed 27 Jun. 2022.

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More Definitions for light-year

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)

More from Merriam-Webster on light-year

Nglish: Translation of light-year for Spanish Speakers

Britannica.com: Encyclopedia article about light-year

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