weak force
Americannoun
-
The fundamental force that acts between leptons and is involved in the decay of hadrons. The weak nuclear force is responsible for nuclear beta decay (by changing the flavor of quarks) and for neutrino absorption and emission. It is mediated by the intermediate vector bosons (the W boson and the Z boson), and is weaker than the strong nuclear force and the electromagnetic force but stronger than gravity. Some scientists believe that the weak nuclear force and the electromagnetic force are both aspects of a single force called the electroweak force.
-
Also called weak nuclear force weak interaction
-
Compare electromagnetic force
Etymology
Origin of weak force
First recorded in 1965–70
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
A Z boson is a neutral elementary particle associated with the weak force.
From Science Daily ● Oct. 6, 2026
A deuteron contains just one proton and one neutron, held together by a relatively weak force.
From Science Daily ● Dec. 27, 2025
Yet the electromagnetic force can, in principle, reach across the universe, whereas the weak force doesn’t even reach across a nucleus.
From Science Magazine ● Mar. 27, 2024
The weak force was the next to join the force family, after scientists developed high-energy particle accelerators.
From Scientific American ● Aug. 19, 2023
They suggested that in addition to the photon, there were three other spin-1 particles, known collectively as massive vector bosons, that carried the weak force.
From "A Brief History of Time: And Other Essays" by Stephen Hawking
![]()
Random Word
Spin the wheel and learn a new word!
Get a wordDefinitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.