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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Today, a single optical fiber in modern submarine cables can carry data equivalent to roughly 150 million simultaneous phone calls at the speed of light, according to the International Cable Protection Committee.
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Mostafa Salem, CNN Money, 17 May 2026
This created a plasma that behaves like an oscillating mirror, and subsequent lasers hitting it are like hitting a mirror moving toward you at nearly the speed of light.
—Ameya Paleja, Interesting Engineering, 14 May 2026
There’s no way that an object, any object, can move through space at speeds that exceed the speed of light.
—Big Think, 1 May 2026
Polaritons move relatively sluggishly—around 100 times slower than the speed of light.
—Adam Kovac, Scientific American, 30 Apr. 2026
See All Example Sentences for speed of light
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Mostafa Salem, CNN Money, 17 May 2026
This created a plasma that behaves like an oscillating mirror, and subsequent lasers hitting it are like hitting a mirror moving toward you at nearly the speed of light.
—Ameya Paleja, Interesting Engineering, 14 May 2026
There’s no way that an object, any object, can move through space at speeds that exceed the speed of light.
—Big Think, 1 May 2026
Polaritons move relatively sluggishly—around 100 times slower than the speed of light.
—Adam Kovac, Scientific American, 30 Apr. 2026
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 20 May. 2026.
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