Phylactery
Gygax knew what it meant, but didn't bother explaining. The 2e authors had no idea, and so made it a Lich's hidden soul receptacle.
Hello adventurers,
I encountered a bunch of CR 1/2 Mooks the other day, and had to crit my way through a dungeon crawl.
What are, in your opinion, the most interesting bits of RPG jargon?
(Actually aren't "psionic" and "psion" terms made up by D&D?)
They are legitimately two different words with not quite synonymous meanings in English. The actual definition of Sorcerer is closer to a D&D warlock, though.wizard vs. sorcerer
Probably borrowed from Michael Moorcock - the struggle between Law & Chaos (with neutrality also in there) was a overaching backdrop for many of his books, an alternative to the classic Good v Evil. Moorcock enjoyed tweaking things, that way.lawful vs. good, chaotic vs. evil (earlier editions definitely treated lawful as the alignment for heroes and chaotic as the alignment for monsters)
Color coding mapping to breath weapons might be D&D. But dragons of specific colors have been significant in heraldry and in myth/legend. The Red Dragon of Wales, for instance.dragons are color-coded for your convenience

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.