I recently finished reading Melissa Mohr's delightful book Holy Sh*t: A Brief History of Swearing. Among other things, it's a fun, light illustration of some of the drivers behind what makes certain words taboo—granted, without discussing much in the way of formal linguistics—and should make apparent, in my view, how arbitrary many of those distinctions are.
To summarize her thesis, she divides curses into the holy and the shit: respectively, words and phrases that invoke religious ideas and bodily/sexual language. In the Middle Ages, religious oaths were thought to be much more offensive because they either forced God to bear witness to a lie, hence deceiving Him, or committed actual physical violence against Jesus, while words like fuck, shit, and cunt were simply the most direct words for their referents. They most likely would not have raised an eyebrow.
During the Renaissance, however, sensibilities began to change. Religious curses, still reviled by some modern believers, nevertheless began to lose some of their shock value, making way for shit-words to claim a measure of notoriety for themselves, eventually culminating in the Victorian Era's extreme animus toward foul language. According to Mohr, this transition continues today, with one notable exception: racial epithets have now basically supplanted both the holy and the shit as the most shocking language.
Anyway, I highly recommend the book, and because I am both a lover of language and an overgrown man-child who's maintained his juvenile sense of humor despite being buffeted by the mentally erosive forces of time, experience, and a joyless commitment to pessimism, I'd like to reproduce a smattering of glorious Victorian sexual euphemisms taken from a chapter in Holy Shit titled "Gamahuche, Godemiche, and the Huffle".
Mouse over the references to see the truly hilarious original wording of selected definitions. Also, some of these words predate the Victorian era, but the chapter seems to imply they would have been in regular, if vulgar, use during Queen Victoria's reign.
Huffle, Bagpipe: blowjob
Gamahuche: fellatio, cunnilingus
Larking: some sources claim fellatio, but Mohr seems to favor Gordon Williams's argument that it means, to put it in words she does not, titty fucking. She also references an engraving called "The Larking Cull" (1800) which shows a man doing just such a thing. You can view it at the British Museum's website!
To Tip the Velvet: either French-kissing or cunnilingus
Covent Garden Ague: venereal disease
Covent Garden Abbess: bawd
Covent Garden Nun: prostitute
Lobcock: a big, rubbery one
Rantallion: I must leave it to Grose here again: "one whose scrotum is so relaxed as to be longer than his penis, i.e. whose shot pouch is longer than the barrel of his piece"
Burning Shame: Grose defines this as "a lighted candle stuck into the parts of a woman, certainly not intended by nature for a candlestick"
The following were all slang words for penis. As with many euphemisms, some of these are more innocuous than others and probably depend largely on context, which might render them either as the uncomfortable, ill-willed curses I referred to in an earlier footnote or simply as crude and goofy:
Euphemisms for vagina:
a woman's Commodity
Euphemisms for sexual intercourse:
Have Your Greens
Bubbies, Diddeys: breasts
Bushelbubby: a woman with large breasts