Preon

Part of speech: noun

Definitions

1. A theoretical elementary particle proposed as a fundamental constituent more basic than quarks and electrons
2. A postulated subatomic entity that would compose known particles like quarks if such a deeper layer of matter exists
3. A conjectured particle that would serve as a building block for standard model particles in certain speculative physics theories

Etymology: The particle physicist Abdus Salam and his colleague Jogesh Pati coined "preon" in 1974, when they proposed that the quarks and leptons of the Standard Model might themselves be built from still more basic particles. They needed a name for these hypothetical building blocks, and they simply attached the prefix "pre-", meaning "before" or "prior to," to the suffix "-on," the ending used in physics for a family of particles, as in "electron," "photon," and "quark" relatives like "gluon." The result names something that would come before the ordinary particles, as if they were the ingredients from which those particles are assembled. The name is therefore a deliberate technical invention rather than a word that evolved over centuries. Its meaning is fixed by the theory it was made for, and it does not come from any older language, so the history is short and fully recorded in one 1974 proposal.