- a hypothetical particle that travels faster than the speed of light.
Origin of tachyon
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- physics a hypothetical elementary particle capable of travelling faster than the velocity of light
C20: from tachy- + -on
Word Origin and History for tachyon
Online Etymology Dictionary, © 2010 Douglas Harper
- A hypothetical subatomic particle that travels faster than the speed of light. Although the principles of relativity forbid the acceleration of a particle past the speed of light, they do not prohibit the existence of particles that have always moved faster than that speed. No such particle has ever been detected.
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