mass·​less | \ ˈmas-ləs How to pronounce massless (audio) \

Definition of massless

: having no mass a massless particle

Examples of massless in a Sentence

Recent Examples on the Web Weinberg showed that special relativity and quantum mechanics put striking restrictions on the interactions of massless particles. Quanta Magazine, 12 Aug. 2021 A few months ago, Chalmers published new research about massless structural batteries to power electric cars. Caroline Delbert, Popular Mechanics, 20 May 2021 Scientists have made a massless structural battery 10 times better than before. Caroline Delbert, Popular Mechanics, 22 Mar. 2021 Difficulty #2: despite our theoretical hopes, gravitons (and photons, and gluons) are all probably massless. Ethan Siegel, Forbes, 9 Apr. 2021 Regular airplanes as well as vertical take off and landing vehicles could turn electric by using massless batteries. Caroline Delbert, Popular Mechanics, 22 Mar. 2021 The universe is awash with these fleeting, almost massless particles, but IceCube is after a rare subset. Daniel Clery, Science | AAAS, 31 Mar. 2021 In the bending of light problem, the sun was modeled identically, but the light was modeled as a massless point traveling at the speed of light (a photon). Tim Childers, Popular Mechanics, 10 Dec. 2020 According to the theory worked out by Dr. Pauli and Enrico Fermi, neutrinos were virtually massless ghost riders of the sky, traveling at the speed of light and rarely interacting with other matter. Dennis Overbye, New York Times, 16 Nov. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'massless.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of massless

1879, in the meaning defined above

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Time Traveler for massless

Time Traveler

The first known use of massless was in 1879

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Dictionary Entries Near massless

Mass John


mass-luminosity law

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Statistics for massless

Last Updated

29 Aug 2021

Cite this Entry

“Massless.” Dictionary, Merriam-Webster, Accessed 27 Sep. 2021.

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