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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Neutrinos are virtually massless particles that stream through the cosmos at nearly the speed of light. Robert Lea, Space.com, 9 Jan. 2026 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 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

Browse Nearby Words

Cite this Entry

“Massless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/massless. Accessed 15 Jan. 2026.

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!