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
The Andromeda galaxy is approximately 2.5 million light-years away from the Milky Way.
—Amaris Encinas, USA TODAY, 22 Jan. 2025
Located about 1,300 light-years from Earth, these young stars, also known as protostars, reside in a hotbed for star formation: the Orion Nebula, which is the nearest massive star-forming region to Earth and is home to hundreds of newborn stars.
—Samantha Mathewson, Space.com, 20 Jan. 2025
But anything outside of that bubble, which is only a few billion light-years on a side, will be gone forever.
—Paul Sutter, Ars Technica, 14 Jan. 2025
Scientists have calculated that anything wider than about 1.2 billion light-years would upset the homogeneous cosmic apple cart.
—Sarah Scoles, Scientific American, 1 Jan. 2025
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Amaris Encinas, USA TODAY, 22 Jan. 2025
Located about 1,300 light-years from Earth, these young stars, also known as protostars, reside in a hotbed for star formation: the Orion Nebula, which is the nearest massive star-forming region to Earth and is home to hundreds of newborn stars.
—Samantha Mathewson, Space.com, 20 Jan. 2025
But anything outside of that bubble, which is only a few billion light-years on a side, will be gone forever.
—Paul Sutter, Ars Technica, 14 Jan. 2025
Scientists have calculated that anything wider than about 1.2 billion light-years would upset the homogeneous cosmic apple cart.
—Sarah Scoles, Scientific American, 1 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 27 Jan. 2025.
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