light speed


: the speed of light
Accelerating particles to near light speed, such machines are ideal for smashing them to make exotic states of matter, blast out new particles, or even search for new dimensions of space.Adrian Cho
also, informal : an extremely fast rate or speed
A Netflix spokesman said it was adding titles at light speed while negotiating daily with studios, which have their own strategy for dealing with online distribution. Josh Quittner

Example Sentences

Recent Examples on the Web Technology is changing at light speed. Tax Notes Staff, Forbes, 18 Apr. 2023 All are powered by radio waves or microwaves that can accelerate particles to near light speed. Chandrashekhar Joshi, Scientific American, 1 July 2021 For example, the turbulent ionized miasma of matter above and below the disk of material around the black hole is infernally hot and contains powerful magnetic fields that can pump vast energies into particles, accelerating them almost to light speed. Phil Plait, Scientific American, 20 Dec. 2022 There are a lot of ways to contemplate what a head-spinning distance 50 AU is, but one of the best is to consider that even moving at light speed, commands radioed up from Earth take more than seven hours to reach the spacecraft. Jeffrey Kluger, Time, 16 Apr. 2021 Congressman Jake Auchincloss delivering the first congressional speech written by artificial intelligence, or A.I. A.I. is evolving at light speed, with profound consequences for our culture, our politics and our national security. ABC News, 2 Apr. 2023 Photons that don’t easily interact with each other, for example, can be used in communication to offer near distortion-free transfer of information at light speed. Tim Newcomb, Popular Mechanics, 23 Mar. 2023 That could then be confirmed once the accelerometers started to detect wave arrivals as the gravitational signal travels at light speed. Kenna Hughes-castleberry, Discover Magazine, 21 Mar. 2023 Vaccines were developed at light speed. Thomas Barta, Forbes, 26 May 2021 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'light speed.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1914, in the meaning defined above

Time Traveler
The first known use of light speed was in 1914

Dictionary Entries Near light speed

Cite this Entry

“Light speed.” Dictionary, Merriam-Webster, Accessed 3 Jun. 2023.

Last Updated: - Updated example sentences
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