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
Suzanne Patterson
Examples of light-year in a Sentence
my sister and I are close in age, but personality-wise, there are light-years between us
Recent Examples on the Web
Tracking changes in a black hole over time In 2019, the Event Horizon Telescope announced the first direct image ever taken of a black hole at the center of an elliptical galaxy, Messier 87 (M87), located in the constellation of Virgo some 55 million light-years away.
—Ars Technica, 31 Jan. 2025
These techniques are designed to frustrate even the immense potential of quantum computing, a technology light-years beyond the electromechanical bombe that Turing used to break the German Enigma cipher.
—IEEE Spectrum, 29 Jan. 2025
The flashes of radio energy emanate from distant galaxies, with the most distant and most powerful ever observed being found 8 billion light-years away and documented in a 2023 study.
—Eric Lagatta, USA TODAY, 27 Jan. 2025
The team traced the repeating fast radio burst to the edge of an 11.3 billion-year-old galaxy 2 billion light-years from Earth.
—Ashley Strickland, CNN, 24 Jan. 2025
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Ars Technica, 31 Jan. 2025
These techniques are designed to frustrate even the immense potential of quantum computing, a technology light-years beyond the electromechanical bombe that Turing used to break the German Enigma cipher.
—IEEE Spectrum, 29 Jan. 2025
The flashes of radio energy emanate from distant galaxies, with the most distant and most powerful ever observed being found 8 billion light-years away and documented in a 2023 study.
—Eric Lagatta, USA TODAY, 27 Jan. 2025
The team traced the repeating fast radio burst to the edge of an 11.3 billion-year-old galaxy 2 billion light-years from Earth.
—Ashley Strickland, CNN, 24 Jan. 2025
See all Example Sentences for light-year
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Cite this Entry
“Light-year.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light-year. Accessed 10 Feb. 2025.
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