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

Definition of massless

: having no mass a massless particle

Examples of massless in a Sentence

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Neutrinos are nearly massless subatomic particles that have no electric charge and therefore interact rarely with their surroundings. Mike Wall, NBC News, "High-energy 'ghost particle' traced to distant galaxy in astronomy breakthrough," 12 July 2018 Models at the time predicted that certain fundamental particles would be massless, but the mechanism that the three physicists proposed explained how these particles could have mass. Steph Yin, New York Times, "Tom Kibble, Physicist Who Helped Discover the Higgs Mechanism, Dies at 83," 19 July 2016 Such flavor changing shows that neutrinos cannot be massless. Adrian Cho, Science | AAAS, "Weighing the universe's most elusive particle," 29 June 2017

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

The first known use of massless was in 1879

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Rhyming Dictionary: Words that rhyme with massless

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