cigars of the beeper:
It seems that with all coin-names, except for nickels and pennies, you can find out what part of the dollar they are.
I think you'd have to be pretty on the ball to know that "dime" meant "a tenth" (from the Anglo-French
disme, pronounced "deem", from Latin
decima), but I suppose that that isn't impossible...!
Interestingly to me, the "modern" decimal currency in Britain is entirely without new nick-names for the coinage. A pound is still a
quid, but that is the
amout, not the pound coin itself (you could give someone a quid in ten-pence pieces, for example).
Rocky:
Don't forget the 'bit' or rather two bits, which is 25 cents.
That's a good one, and virtually impenetrable as a name, until you think of pirates...!
Pirates, at least in story-books, are reputed to be interested mainly in "pieces of eight", the old Spanish dollar, worth eight reales. If you cut a Spanish dollar into eight pieces (see where this is going...?), you had eight "bits" - so a quarter of a dollar was two reales, or "two bits", a name which stuck when America adopted its own dollar coinage.
The single "bit" dropped out of usage in America as there was no coin worth an eighth of a dollar, or 12.5 cents (and why would there be - it was a decimal system, wasn't it? Well see below...); however, it hung around for a while in the term "short bit" (or ten cents) and "long bit", which was 15 cents.
Eventually even these disappeared, but "two bits" hangs around on the fringes, and pops up from time to say hello.
So eighths of U.S. dollars went out with the abandoning of the Colonial Spanish dollar, and the introduction of decimal currency? Well, not quite...
For some arcane reason which escapes me, the New York Stock Exchange kept on using eighths of dollars to list stock prices for a few years more... right up until 1997, as it happens, at which point they went
mad, and started using 16ths of a dollar (crazy, or what?)... Then they came to their senses, and have been decimal since 2001.
On the subject of coin names, in the U.K. there was a joke that circulated during the "reign" of Margaret Thatcher, the Conservative Prime Minister, that the pound coin should be called a "Maggie", because it was "hard and brassy and thought it was a sovereign" (a play on the idea that Mrs. Thatcher's slightly imperious manner made her unapproachable and gave her an unwarranted regal air, making her like a queen, and that the new coin was designed to resemble an old gold sovereign coin).