fifth force


noun
  1. a theoretical force in nature in addition to the strong and weak forces, gravitation, and the electromagnetic force.

Origin of fifth force

1
First recorded in 1975–80

Words Nearby fifth force

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

British Dictionary definitions for fifth force

fifth force

noun
  1. a hypothetical non-Newtonian repulsive component of the force of gravity, postulated as an addition to the four known fundamental forces (gravitational, electromagnetic, strong, and weak)

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for fifth force

fifth force

[ fĭfth ]


  1. Any of various hypothetical, very weak forces thought to cause bodies to repel each other. Such forces are occasionally considered as a solution to unexpected deviations in the measured value of the gravitational constant or to explain the apparent acceleration of very distant galaxies away from earth.

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