speed of light
noun phrase
: a fundamental physical constant that is the speed at which electromagnetic radiation propagates in a vacuum and that has a value fixed by international convention of 299,792,458 meters per second
—symbol c
Examples of speed of light in a Sentence
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Traveling at the speed of light, this radiation reaches Earth almost instantly, ionizing the upper atmosphere.
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Daisy Dobrijevic, Space.com, 28 Mar. 2025
Meanwhile, the longer, bigger flares may occur due to magnetic reconnection events, or when two different magnetic fields collide near the black hole and release energetic particles moving near the speed of light.
—Ashley Strickland, CNN, 19 Feb. 2025
They have been directed to provide a comprehensive architecture within 60 days — which is really the speed of light in U.S. defense contracting terms.
—James Stavridis, The Mercury News, 15 Feb. 2025
The particle, a type of neutrino, arrived at Earth at nearly the speed of light and with 30 times the energy of the previous most energetic neutrino ever glimpsed.
—Robert Lea, Space.com, 12 Feb. 2025
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Daisy Dobrijevic, Space.com, 28 Mar. 2025
Meanwhile, the longer, bigger flares may occur due to magnetic reconnection events, or when two different magnetic fields collide near the black hole and release energetic particles moving near the speed of light.
—Ashley Strickland, CNN, 19 Feb. 2025
They have been directed to provide a comprehensive architecture within 60 days — which is really the speed of light in U.S. defense contracting terms.
—James Stavridis, The Mercury News, 15 Feb. 2025
The particle, a type of neutrino, arrived at Earth at nearly the speed of light and with 30 times the energy of the previous most energetic neutrino ever glimpsed.
—Robert Lea, Space.com, 12 Feb. 2025
See All Example Sentences for speed of light
Cite this Entry
“Speed of light.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/speed%20of%20light. Accessed 19 Apr. 2025.
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