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 Tarantula spins its web in the Large Magellanic Cloud, which is a satellite galaxy of our Milky Way, 160,000 light-years from us.
—Keith Cooper, Space.com, 14 Feb. 2025
Neutrinos are ghostly subatomic particles that can travel in a straight line for billions of light-years, passing unhindered through galaxies, stars and anything else in their path.
—Doyle Rice, USA TODAY, 13 Feb. 2025
In fact, the superstructure is estimated to hold an almost inconceivable 200 quadrillion (that's 200 followed by 15 zeros) times the mass of the sun and is more than 1.3 billion light-years long, larger than the Milky Way.
—Thomas G. Moukawsher, Newsweek, 12 Feb. 2025
The ring itself is made of distorted light from a distant galaxy, located 4.42 billion light-years away.
—Ashley Strickland, CNN, 11 Feb. 2025
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Keith Cooper, Space.com, 14 Feb. 2025
Neutrinos are ghostly subatomic particles that can travel in a straight line for billions of light-years, passing unhindered through galaxies, stars and anything else in their path.
—Doyle Rice, USA TODAY, 13 Feb. 2025
In fact, the superstructure is estimated to hold an almost inconceivable 200 quadrillion (that's 200 followed by 15 zeros) times the mass of the sun and is more than 1.3 billion light-years long, larger than the Milky Way.
—Thomas G. Moukawsher, Newsweek, 12 Feb. 2025
The ring itself is made of distorted light from a distant galaxy, located 4.42 billion light-years away.
—Ashley Strickland, CNN, 11 Feb. 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 20 Feb. 2025.
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