\ ˈlīt-ˌyir
\
\
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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“Light-year.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light-year. Accessed 5 Mar. 2021.
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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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The first known use of light-year was in 1867
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