In searching for "carboy" hoping to find standard volume (if any) I found a site
about brewing with a lot of interesting words. A sample:
The bung, or cork of a beer barrel. It is pierced so that a "spile" can be inserted into it.

Spraying, or rinsing the spent grains in the mash in order to separate the sugars from the husks of the barley after mashing

Specific Gravity
The measure of a substance's density when compared to that of water. Water's density at 60 degrees F is given the value
of 1.000.

A spear made of wood about 2 inches long. It is fitted into the shive of a beer, or ale, cask. A soft spile will allow venting of
internal cask pressure. A hard spile will reseal the cask.