weak force
noun
: 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 1a(2), strong forceCite this Entry
“Weak force.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/weak%20force. Accessed 7 Jul. 2026.
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