mass·​less ˈmas-ləs How to pronounce massless (audio)
: having no mass
a massless particle

Example Sentences

Recent Examples on the Web This is, of course, exactly what does happen with the strong nuclear force; gluons are massless, but the strong force is confined and therefore short-range. Sean Carroll, Discover Magazine, 22 Nov. 2012 Neutrinos are nearly massless particles produced in the sun and in energetic events like supernovas, colliding stars, and gamma-ray bursts. Korey Haynes, Discover Magazine, 23 May 2019 If a certain symmetry in the models was broken, the massless partner would go away, leaving only a massive one. Jennifer Ouellette, Ars Technica, 9 Sep. 2022 According to the Standard Model, two gluons, the massless particles that glue together atomic nuclei, easily interact with each other to double their own number, becoming four gluons. Katie Mccormick, Quanta Magazine, 1 Aug. 2022 Theory predicted that neutrinos would be completely massless. Joanna Thompson, Scientific American, 15 June 2022 Electromagnetic force was well explained by quantum field theory, which pictured attraction or repulsion as an exchange of massless particles—photons—able to travel across unlimited distances. Andrew Crumey, WSJ, 3 June 2022 One main challenge is physics: Nothing can travel faster than the speed of light—300 million meters per second for massless particles. Steven Carlini, Forbes, 18 May 2022 Weinberg showed that special relativity and quantum mechanics put striking restrictions on the interactions of massless particles. Quanta Magazine, 12 Aug. 2021 See More

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.

Word History

First Known Use

1879, in the meaning defined above

Time Traveler
The first known use of massless was in 1879

Dictionary Entries Near massless

Cite this Entry

“Massless.” Dictionary, Merriam-Webster, Accessed 20 Mar. 2023.

Last Updated: - Updated example sentences
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