A word not to use, if you want to live

Forrest Wickman has a Slate article about the C-word:

The satirical newspaper the Onion offered a rare apology yesterday after it joked that nine-year-old actress Quvenzhané Wallis was “kind of a cunt, right?”
Has that word always been so patently offensive?
No. In Middle English the word could be used as a standard term for the female genitalia, in a manner that was quite matter-of-fact. The earliest instance of the word recorded in the Oxford English Dictionary is actually from the name of a thirteenth-century London street, Gropecuntelane. The name appears to have been quite literal, and there was at least one other red-light district of the same name, in Oxford. One of the next recorded uses of the word comes from a circa-1400 surgery manual and uses the word much like vagina might be used today: “In women the neck of the bladder is short, and is made fast to the cunt.” Others have noted that some people in the thirteenth and fourteenth centuries also had the word in their names, in a way that seems unlikely today: some men and women at that time included Bele Wydecunthe, Robert Clevecunt, and Gunoka Cuntles. Indeed, as Geoffrey Hughes wrote in his book Swearing, there were many such colorful names, but “the days when the dandelion could be called the pissabed, a heron could be called a shitecrow, and the windhover could be called the windfucker, have passed away with the exuberant phallic advertisement of the codpiece.”
The word became more offensive over the next few centuries. While Chaucer used the variant quaint in both the Miller’s Tale (“he caught her by the quaint”) and the Wife of Bath’s Tale (“you hall have quaint right enough at eve”), Shakespeare dared only to slyly allude to the word. In Hamlet, for example, when Ophelia tells Hamlet that, yes, he can lie on her lap, Hamlet puns in his response: “Do you think I meant country matters?” In Twelfth Night, Shakespeare finds a coded way to spell out the word, when Malvolio recognizes his lady’s “C’s, her U’s, ‘n’ her Ts.” (“Thus makes her great P’s,” he continues, in what amounts to an elaborate potty joke.)
If, in Shakespeare’s time, the word was becoming too obscene to utter in public, by the end of the eighteenth century it was truly taboo. When Robert Burns’ printed the old Scottish folk song Yon, Yon, Yon, Lassie, in 1796, the word appeared only as “c—t.” In his 1811 Dictionary of the Vulgar Tongue, Francis Grose defined “c**t” as “a nasty name for a nasty thing”, while elsewhere he bleeped it out entirely (“****”), or referred to it only as “the monosyllable.” (Lest you think him just a prude, Grose noted that others went even further, rendering the word constable as thingstable; Grose called this “a ludicrous affectation of delicacy”.) By the early twentieth century, cunt had begun to be used as an insult, and it was also around this time that language taboos shifted from religious profanity to vulgar sexual and scatological language. This perception that it's one of the most taboo words continues today: In a 2000 BBC study of the most offensive words, it ranked Number One, ahead of motherfucker, fuck, and even nigger.
Why has cunt become so much more taboo than, say, snatch or pussy? The main reason may simply be that it’s blunt. Linguists note that, unlike those other words for the female genitalia— whose origins are all Latinate, euphemistic, or diminutive— cunt is plain and Anglo-Saxon. There is also the sound of the word. Many of the most taboo words, in addition to generally being Anglo-Saxon in origin, are monosyllables with short vowels, such as shit, piss, fuck, and cock. These are considered more offensive than words of the same meaning, like poopy, pee, screw, and willy. In fact, one of the only other words to share many of these characteristics is twat, which is also often considered highly offensive, though its origins are more uncertain.

Rico says it's a perfectly good word to describe some people, but he suggests you wear something bullet-proof around his ladyfriend... (And it is not a nasty thing, either.)