tardyon

Blend of tardy +‎ tachyon or tardy +‎ -on.

tardyon (plural tardyons)

1. (physics) Any particle with non-zero mass (i.e. one that travels more slowly than the speed of light).
   • 1972, Isaac Asimov, Asimov's Guide to Science:

     One, our own, is the tardyon-universe, in which all particles go at subluminal velocities and may accelerate to nearly the speed of light.

   • 1988, Nick Herbert, Faster Than Light: Superluminal Loopholes in Physics:

     Just as brute force cannot make a tachyon out of a tardyon...

• (particle with non-zero mass): bradyon, ittyon, massive particle

• tardyonic

• tachyon
• luxon

• Drayton