Word To Use Today: jackpot.

 Three questions arise with this word: who is Jack, why is he in a pot, and why should anyone want to hit it, anyway?

It has an interesting history, does the word jackpot, because originally a jackpot was a Bad Thing...Well, it was if you were a criminal, anyway, because in criminal slang a jackpot was an arrest, or some other kind of bad trouble.

The good-fortune type of jackpot involves the kind of jack you find on playing cards.

Our current meaning of the word jackpot became came into being as a term for a large pay-out on an arcade slot machine, but before that it was a term from the card game of draw-poker. 

This is the only explanation of the term I've been able to find, and I don't understand it at all. Even my poker-playing friends don't really understand it, but here it is, anyway:

The regular Draw-Poker game is usually varied by occasional Jack-Pots, which are played once in so many deals, or when all have refused to play, or when the player deals who holds the buck, a marker placed in the pool with every jack-pot. In a jack-pot each player puts up an equal stake and receives a hand. The pot must then be opened by a player holding a hand of the value of a pair of knaves (jacks) or better. If no player holds so valuable a hand the deal passes and each player adds a small sum to the pot or pool. When the pot is opened the opener does so by putting up any sum he chooses, within the limit, and his companions must pay in the same amount or "drop." They also possess the right to raise the opener. The new cards called for are then dealt and the opener starts the betting, the play proceeding as in the regular game. 

That's from the 1911 Encyclopedia Britannica. I have the complete set, and they're brilliant for standing on when decorating the stairs

I honestly don't know why anyone should want to hit the jackpot; but I suppose it's just like hitting the road, something you do with understandable enthusiasm.

Word To Use Today: jackpot. A jack was originally just a word for a man. The word started off as jakke in the 1500s, which was short for Jankin, which was short for Jack (except, of course, longer). The word pot was pott in Old English, and might, entertainingly, come form the Latin pōtus, which means drink.