Yours, Etc.: Origins and Uses of 8 Sign-Offs
"small cask, fourth part of a barrel," late 14c., apparently from Middle Dutch *vierdekijn, diminutive of vierde, literally "fourth, fourth part" (see fourth).
Used only in John 2:6; the Attic amphora, equivalent to the Hebrew bath (q.v.), a measure for liquids containing about 8 7/8 gallons.