>>I assume this one should be "billiard"... which would probably translate to "pool" here.
>
>Yea, even though billiard balls have no numbers on them

And they play pool without checking whether the water in it is cold or not...

And waterpolo is the most expensive sport, because so many horses drown.

Kidding aside - my wife has a hunch that the "billion" came to mean 1e9 in the States when they had the first guy who had that much cash, and some reporter (or the guy him/herself) wanted a catchy word. Neither would be a candidate for good knowledge of world standards or literacy.