Pionic

Part of speech: adjective

Definitions

1. Relating to pions, the lightest type of meson, which are subatomic particles made of a quark and an antiquark
2. Describing something connected with pions, the short-lived particles that mediate the strong nuclear force between nucleons
3. Of or concerning the pion, a subatomic particle that carries the residual strong interaction between protons and neutrons

Etymology: "Pionic" is formed by adding the suffix "-ic" to "pion," the name of a subatomic particle. "Pion" is itself a shortened form of "pi-meson," coined by physicists in the late 1940s for a particle that mediates the strong nuclear force between protons and neutrons. The Greek letter pi was chosen because it is the initial of "pi" and echoes the older word "meson," which had been derived from the Greek "mesos," meaning "middle," because the particle's mass fell between that of an electron and a proton. The suffix "-ic" comes from Greek "-ikos" through Latin and French, and it turns a noun into an adjective meaning "relating to" or "characteristic of." So "pionic" simply means "relating to pions," and it is used in phrases such as "pionic atoms," which are atoms in which a negatively charged pion has replaced an electron. Like many scientific terms of the twentieth century, it was built from existing parts rather than inherited from ancient languages.