weak force


: a fundamental physical force that governs interactions between hadrons and leptons (as in the emission and absorption of neutrinos) and is responsible for particle decay processes (such as beta decay) in radioactivity, that is 10-5 times the strength of the strong force, and that acts over distances smaller than those between nucleons in an atomic nucleus

called also weak interaction, weak nuclear force

compare electromagnetism sense 2a, gravity sense 3a(2), strong force

Examples of weak force in a Sentence

Recent Examples on the Web Their efforts have led to the Standard Model of particle physics, which describes the most fundamental ingredients of matter (leptons and quarks) and the forces that control them (the electromagnetic, strong and weak forces). Daniel Garisto, Scientific American, 13 Dec. 2023 The neutral charge is important because gravity is a weak force. Stephanie Pappas, Scientific American, 27 Sep. 2023 Gravity is such a weak force that even the best experiments already have a lot of jiggle in them. Thomas Lewton, Quanta Magazine, 10 July 2023 Their aim was not to fight the Taliban, perceived at the time as a weak force. Rory Stewart, Foreign Affairs, 8 Oct. 2021 Their clinging power resides in microscopic, hair-like structures on their toes that employ what are called van der Waals forces – a weak force that draws molecules together. Carl Engelking, Discover Magazine, 27 Apr. 2015 But Salam, a practicing Muslim and one of the physicists to mathematically unify two of the fundamental forces of nature—electromagnetism and the weak force, which governs radioactivity—identified with Polkinghorne’s quest. Zeeya Merali, Discover Magazine, 3 Mar. 2011 One of the products of a radioactive decay (which is driven by the weak force) is a neutrino, so nuclear reactors produce copious amounts of these particles. John Timmer, Ars Technica, 11 Jan. 2023 The Tevatron collider in Illinois smashed its last protons a decade ago, but its handlers have continued to analyze its detections of W bosons — particles that mediate the weak force. Natalie Wolchover, Quanta Magazine, 22 Dec. 2022 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'weak force.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1968, in the meaning defined above

Time Traveler
The first known use of weak force was in 1968

Dictionary Entries Near weak force

Cite this Entry

“Weak force.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/weak%20force. Accessed 29 Feb. 2024.

Kids Definition

weak force

: a fundamental force experienced by elementary particles that causes some forms of radioactivity and also causes some types of particles to break down into other particles

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