Butt (unit)
The butt is an obsolete English measure of liquid volume equalling two hogsheads, being between  by various definitions. Equivalents
A butt approximately equated to  for ale or  for wine (also known as a pipe), although the Oxford English Dictionary notes that "these standards were not always precisely adhered to". The butt is one in a series of English wine cask units, being half of a tun. See also
 English wine cask units § Pipe or butt

References

Units of volume