“Bad language” was a relatively accepted aspect of English even in Shakespeare’s day — not that he actually used the most forbidden words, but he clearly alluded to them (“Do you think I meant country matters?”), and he revelled in vigorous insults. In King Lear, when Oswald asks the Earl of Kent, “What dost thou know me for?” the latter replies, “A knave; a rascal; an eater of broken meats; a base, proud, shallow, beggarly, three-suited, hundred-pound, filthy, worsted-stocking knave; a lily-liver’d, action-taking, whoreson, glass-gazing superserviceable, finical rogue; one-trunk-inheriting slave; one that wouldst be a bawd in way of good service, and art nothing but the composition of a knave, beggar, coward, pander, and the son and heir of a mongrel bitch; one whom I will beat into clamorous whining, if thou deny the least syllable of thy addition.” He follows that up with “Draw, you whoreson cullionly barbermonger! Draw!” Clearly both playwright and audience enjoyed a good blackguarding, and there was no sense that public speech had to be decorous.
[An example of an insult in] British English: a few bricks short of a full load: This is the basic form of an insult meaning ‘stupid, dim-witted, not quite right in the head, not sensible’ that has many variants beginning “A few … short of …”: a few pints short of a gallon, a few sandwiches short of a picnic.
American English: silk stockings: This term, at the end of the eighteenth century simply a reference to the well-to-do in the brand-new United States, a century later had insulting overtones. It had plenty of company: the upper crust (a term used from the 1830s on) were also called fancy-pants, high-hats, Mr. Moneybags (or Gotrocks), snoots, stuffed shirts, and (in New York City, where their natural habitat was Fifth Avenue) Avenoodles (a term used by Walt Whitman in 1856 and still in use in 1900).
Glaswegian/Scottish English: like a fart in a trance: This Glaswegian expression is used of a dreamy person who always seems at a loss what to do. “Away oot fur gooness sake instead a hingin aboot the house lik a fart in a trance!” — Robert Vanderplank, from his book Uglier Than a Monkey’s Armpit (read for free)