Why Do We Say 'Put up Your Dukes'?
If a phrase seems inexplicable, there's a chance that it comes from rhyming slang
Words come about in a number of ways, but probably none is so creative as the means referred to as rhyming slang. What usually happens in rhyming slang is that a phrase is used as slang for a word that rhymes with one part of the phrase. So loaf of bread may be used to mean head. But what often happens is that the phrase is then shortened to one word—and not the one that rhymes—and you're left with a slang synonym that has no obvious relationship to the main word, and now loaf means head.
Etymologists think this is probably how we got the word dukes used to refer to fists, as in "put up your dukes." Fork was slang for "hand" or "fist," and the phrase "dukes of York" was created as rhyming slang for "fork." So, instead of telling someone to "put up your forks," you might say "put up your dukes of York!" Eventually, this was shortened to "put up your dukes."
Another term probably from rhyming slang is eighty-six, a term that can be used in a number of situations. A bar customer who's been eighty-sixed isn’t being served any more alcohol. An order at a restaurant can be eighty-sixed if a customer changes his or her mind and decides to order something different instead. An item at a restaurant that the kitchen has run out of is also said to be eighty-sixed. Whatever the situation, the probable origin of eighty-six is that it's rhyming slang for "nix."
And then there's the somewhat rude sound that kids—and others—like to make with their tongue sticking out. You know, the one called a raspberry. Why is it called that? Well, "raspberry" in this case is short for "raspberry tart." You can guess the rest.