On most computers running the UNIX operating system, there's a directory named /etc. Some people pronounce that directory name as "etcetera"; others simply say /'Et si/. Some may even spell it out as /'i 'ti 'si/. Another standard UNIX directory name, /usr, is generally pronounced like "user," but sometimes spelled out to avoid confusion with a directory named /user... There are occasional heated debates between the proponents of /gIf/ and the proponents of /dZIf/, even though they're both talking about GIF, the Graphics Interchange Format that's widespread on the Web. (A new graphics standard, Portable Network Graphics, has pre-emptively defined its abbreviation, PNG, to be pronounced /pIN/, to avoid just such arguments and confusion.)
"OS" (short for Operating System) is variously pronounced /As/ or /oUs/, or (as the New Hacker's Dictionary has it) just spelled out /'oU 'Es/. I've heard someone say /dAz/ for DOS, more commonly pronounced /das/. And the most common text editor in UNIX systems, "vi," is usually spelled out, but some enterprising jokesters refer to it as "6," pretending to read it as Roman numerals.
Speaking of things Roman, and of "etc.," there are a few Latin abbreviations which have become so common in English as to hardly be noticed as Latin. Outside of the computer context, etc. is short for "et cetera," meaning "and so on"—though more and more people say "ek cetera" these days. I always used to mix up i.e. and e.g., until a friend told me what they stood for: "id est" ("that is") and "exempli gratia" ("by the grace of example," or loosely "for example," though my friend originally taught it to me as "exemplar gratis," and translated it as "free example"—as in, "hey, free example!"), respectively.
There's one Latin abbreviation which has become so common it's turned into an independent character: I refer, of course, to the lovely and talented ampersand, &, which began life as a ligature of et, Latin for "and." (Even in modern typeset ampersands you can still sort of see the e on the left, and the t made by the crossing lines on the lower right; some fancy ampersands look more explicitly like an e with a crossbar on the end). The word "ampersand" derives from "and per se and," a sort of self-referential definition of the character. (Anyone who tries to tell you that the term comes from an early typesetter named Amper ("Amper's and") is either pulling your leg or just mistaken.)
There are a host of other Latin abbreviations that were once widely used in English but which have fallen out of favor except in certain areas of academia: viz. ("videlicet," "namely"—it acquired the final z through the same fascinating process by which "oz." for "ounce" acquired its z (both zs were originally ampersand-like ligatures for "et," even though they indicated the Latin suffix "-que")), q.v. ("quod vide," "see which"), ibid. ("ibidem," "same [source] as preceding [footnote]"), op. cit. ("opere citato," "same work"), pass. ("passim," "scattered [references] throughout"), et al. ("et alia," "and others"). (Not to be confused with "inter alia," "among other things.")
There are some lovely Latin phrases that would be of great use in English if only people knew them. I already mentioned "mutatis mutandis" ("with the necessary changes being made") in a previous column; I'm also quite fond of "hapax legomenon" ("a word occurring only once in a document") (saying that phrase always makes me want to start singing the Muppet Show song "Manna Manna") and "ex tempore" (which literally means "out of time," but in the sense of "on the spur of the moment"). For more, I recommend poking through the "foreign words and phrases" sections at the back of some dictionaries (such as Webster's Ninth New Collegiate)
One last item, while I'm talking about Latin. In James Joyce's A Portrait of the Artist as a Young Man, the protagonist's friend Cranly is fond of saying ordinary things translated into Latin. At one point, for instance, he says, "Nos ad manum ballum jocabimus," which one edition's footnotes translate as "Let's go play handball." At another point, Cranly asks, "Are you in bad humour?" Stephen (the protagonist) says no, to which Cranly replies: "Credo ut vos sanguinarius mendax estis [...] quia facies vostra monstrat ut vos in damno malo humore estis." Which, translated into British schoolboy English, could be rendered: "I believe you're a bloody liar, because your face shows you're in a damned bad humour." Of course in Latin "sanguinarius" doesn't actually mean "bloody" in the all-purpose British swear-word sense of the term; Cranly just likes to play games with the language. So next time you think someone's telling you an untruth, you might try accusing them of being a "sanguinarius mendax."
That's all for this week—I'm ex tempore.
Thanks to Kendra Eshleman, and the Humez brothers (authors of ABC Et Cetera, from which I cribbed part of the abbreviation discussion), for help with this week's column.