Below is a brief definition of the name of each of the most common sizes. I've included 'bottle' and 'magnum' for completeness.
As well as the eight sizes listed above, there are a couple of other named sizes which, although rare, are nevertheless genuinely recognized. These are:
- Solomon : which contains 28 bottles
- Primat : which contains 36 bottles
Since the larger sizes are so unwieldy (the Primat weighs 143 pounds), the secondary fermentation stage of Champagne is usually undertaken in magnums which are then decanted into the larger sizes. This inevitably incurs a greater risk of oxidization and infection and therefore a greater risk of an inferior product.
The source of much of this information, the 'Bottle Sizes' page at http://www.champagnemagic.com/sizes.htm suggests the following extremely lame mnemonic for the more common large bottle sizes :
My Judy Really Makes Splendid Belching Noises
Perhaps 'Judy' has a meaning that I'm not aware of.