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
Everyone on Earth would clock you at the speed of light, but from your reference frame, time would completely stop.
—
Jarred Roberts, The Conversation, 20 May 2025
The field change would manifest in a quantum bubble, which, if big enough, could expand at the speed of light, ultimately making matter—and therefore life—impossible.
—Jeanna Bryner, Scientific American, 20 May 2025
The eruption sent a blast of X-rays and extreme ultraviolet radiation hurling toward Earth at the speed of light, rapidly ionizing the upper atmosphere.
—Daisy Dobrijevic, Space.com, 14 May 2025
This type of technology supports your consumers at the speed of light, enables robust e-commerce engagement, makes connections where humans may be unable to and provides many other benefits.
—Tara Duke, Forbes.com, 14 May 2025
See All Example Sentences for speed of light
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Jarred Roberts, The Conversation, 20 May 2025
The field change would manifest in a quantum bubble, which, if big enough, could expand at the speed of light, ultimately making matter—and therefore life—impossible.
—Jeanna Bryner, Scientific American, 20 May 2025
The eruption sent a blast of X-rays and extreme ultraviolet radiation hurling toward Earth at the speed of light, rapidly ionizing the upper atmosphere.
—Daisy Dobrijevic, Space.com, 14 May 2025
This type of technology supports your consumers at the speed of light, enables robust e-commerce engagement, makes connections where humans may be unable to and provides many other benefits.
—Tara Duke, Forbes.com, 14 May 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 28 May. 2025.
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