"tachyon." YourDictionary, n.d. Web. 18 January 2019. <https://www.yourdictionary.com/tachyon>.
tachyon. (n.d.). Retrieved January 18th, 2019, from https://www.yourdictionary.com/tachyon
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.