Now, now… if you thought I was going to be rude, you don’t know me very well. While I am certain that the term “butt” has led to countless jibes and jokes down through the centuries, it is (among other things) in fact an English measuring unit for wine. A Buttload is a unit for liquids which contains 126 gallons (~476 litres) which is one-half tun (252 gallons / 953 litres), and equivalent to the pipe (the latter also referred to the large container used for storing liquids or foodstuffs; now we rather use the terms cask or vat). That they needed a term for a unit of wine that massive may seem odd at first; but when you consider that the water they had to drink was the same water that flowed downhill from the landlord’s latrine, the cows in the pasture, and the washerwoman upstream, wine, beer and ale (depending on which harvest climate you lived in) was by far the safest thing to drink. If wine was available in your area, it was stored in barrels and thus was drunk relatively young; also, to counter the effects of drinking it at every meal, wine was often diluted 4 or 5-to-1 with water; that took all of the buzz out of it (and added who knows how many bugs that they were drinking wine to avoid in the first place…). Now you know. What a buttload off my mind… I think it’s time for a glass of (undiluted) wine.
Stephanie Huesler 
For a delightful insightful read of all things wine, I recommend Brian Doyle’s “The Grail.” That’s where I first learned of the units you mention in this post. Good stuff.
I see what you did there.
I’ll check it out! We’ll be in a wine-growing area for holidays, so it might be the perfect read. 😉