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\Definition of light-year
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“Light-year.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light-year. Accessed 21 Feb. 2020.
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light-year
nounEnglish Language Learners Definition of light-year
See the full definition for light-year in the English Language Learners Dictionary
light-year
nounKids Definition of light-year
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Time Traveler for light-year
The first known use of light-year was in 1867
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