massless

adjective

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

Examples of massless in a Sentence

Recent Examples on the Web
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Successful sea trial Nearly massless and electrically neutral, neutrinos are born in violent events like nuclear reactions inside stars. Mrigakshi Dixit, Interesting Engineering, 17 Oct. 2025 Fermi hypothesized that some new force could change a proton into a neutron, or vice versa, and, in the process, release an electron and a nearly massless particle called a neutrino. Paul Sutter, Space.com, 14 Oct. 2025 Relativity does indeed state that an object with non-zero mass cannot go at the speed of light, and even massless objects cannot go faster than light. Don Lincoln, Big Think, 29 Aug. 2025 Neutrinos are virtually massless subatomic particles with no charge. Jay Kakade july 20, New Atlas, 20 July 2025 See All Example Sentences for massless

Word History

First Known Use

1879, in the meaning defined above

Time Traveler
The first known use of massless was in 1879

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Cite this Entry

“Massless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/massless. Accessed 27 Oct. 2025.

Last Updated: - Updated example sentences
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