It's a twelfth of a troy pound, or Roman libra (lb).
These two episodes from The History of English podcast trace these seemingly arbitrary units through history and give them some context. My favorite is the derivation of 5280 feet per mile. Also, that "mark twain" is a depth sounding of two fathoms.
http://historyofenglishpodcast.com/2018/07/26/episode-114-th... http://historyofenglishpodcast.com/2018/08/21/episode-115-th...
We don't really use pints for measuring anything else these days.
That's about 50ml more than I'm used to getting when I order a "pint".
And of course 4 quarts to the gallon and two pints to the quart.
Otherwise like in the US in what is commonly known as the English system there is only 3785 mL to the gallon.
A quart is about the maximum amount of whiskey one can drink without dying.
A pint's a pound, the world around.
My favorite is the cord, which is 128 cubic feet, or more often a stack of firewood 4 feet tall by four feet wide by eight feet long.
Or, ounces: How many ounces in a gallon? A pound? And how many _kinds_ of ounces are there, anyways?
Fun fact: The term “ounce” is of Latin origin from the word “uncia” which means “a twelfth part.” http://www.differencebetween.net/science/mathematics-statist... So...what's an ounce a twelfth of?
Or, say, a pint. What's the definition of a pint?