X, x: The origins are in dispute whether the Greeks themselves invented the letter or adapted it from the Semitic samek,“fish.” The confusion over the letter’s origin is compounded by the fact samek looks nothing like a fish, and indeed seems to be adapted from an Egyptian hieroglyph djed, which resembles a pillar or scaffold and represented the backbone of the god Osiris. In Greek, samek lost two of its cross-bars, becoming a simple cross, and fell to its side. In Western Greek, the letter was ksi and pronounced like the English X; Eastern Greek, however, which became the dominant dialect, called the letter khi and pronounced it /kh/. English is the distinct loser by adopting the Western Greek pronunciation. Had we done otherwise, XING would not be a bastard expediency of signage, but a legitimate abbreviation, and the words Christ, cross, and crucify would all begin with a cross.
xenos-: “Stranger,” from which xenophobe, “fear of foreigners.”