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
Recent Examples on the Web
But even this monstrous black hole can't stomach so much matter, leading to some serious indigestion in the form of outflows travelling at around 0.27 times the speed of light.
—
Robert Lea, Space.com, 23 June 2025
Solar flares emit radiation, mostly in the form of ultraviolet light and X-rays, that can hurtle toward Earth at the speed of light.
—Eric Lagatta, USA Today, 19 June 2025
The radio signals will hurtle away at the speed of light, or a mind-blowing 670 million mph.
—Marcia Dunn, Los Angeles Times, 27 May 2025
Think about it – all of this has happened at roughly the speed of light.
—John Werner, Forbes.com, 4 June 2025
See All Example Sentences for speed of light
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Robert Lea, Space.com, 23 June 2025
Solar flares emit radiation, mostly in the form of ultraviolet light and X-rays, that can hurtle toward Earth at the speed of light.
—Eric Lagatta, USA Today, 19 June 2025
The radio signals will hurtle away at the speed of light, or a mind-blowing 670 million mph.
—Marcia Dunn, Los Angeles Times, 27 May 2025
Think about it – all of this has happened at roughly the speed of light.
—John Werner, Forbes.com, 4 June 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 3 Jul. 2025.
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