Quiz: Remember the definition of mal de mer?
slang for "quiet," in phrase on the q.t., attested from 1874. Phrase on the quiet appears from 1847.
qt or qt.
Abbreviation of quart
unit of capacity in the British Imperial and U.S. Customary systems of measurement. For both liquid and dry measure, the British system uses one standard quart, which is equal to two imperial pints, or one-fourth imperial gallon (69.36 cubic inches, or 1,136.52 cubic cm). The U.S. system has two units called a quart, one for liquid measure and a slightly larger unit for dry measure. The U.S. liquid quart is equal to two liquid pints, or one-fourth U.S. gallon (57.75 cubic inches, or 946.35 cubic cm); and the dry quart is equal to two dry pints, or 132 bushel (67.2 cubic inches, or 1,101.22 cubic cm).