[ tak-ee-on ]
/ ˈtæk iˌɒn /

noun Physics.

a hypothetical particle that travels faster than the speed of light.

Origin of tachyon

First recorded in 1967; tachy- + -on1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

British Dictionary definitions for tachyon

/ (ˈtækɪˌɒn) /


physics a hypothetical elementary particle capable of travelling faster than the velocity of light

Word Origin for tachyon

C20: from tachy- + -on
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 tachyon

[ tăkē-ŏn′ ]

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.