- quartA unit of liquid capacity equal to two pints; one-fourth (quarter) of a gallon. Equivalent to 1.136 liters in the UK and 0.946 liter (liquid quart) or 1.101 liters (dry quart) in the U.S.
- quartoA size of paper (7.5"-10" x 10"-12.5" or 190-254 x 254-312 mm). Formed by folding and cutting one of several standard sizes of paper (15"-20" x 20"-25" or 381-508 x 508-635 mm) twice to form 4 leaves (eight sides).
- cotoA traditional Spanish unit of length, equivalent to about 10.4 cm.
- cuartoA traditional Spanish unit of dry measure, equivalent to about 27.8 L.
- quartaA traditional Portuguese unit of dry measure, equal to 3.2–4.8 L in different 19th-century contexts.
- cuartillaA traditional Spanish unit of dry measure, equivalent to about 13.9 L.
- cuartilloA traditional Castilian unit of dry measure, equivalent to about 1.2 L.
- quadroonA person considered three-fourths white, having one non-white grandparent.
- quartanebutane
- quartarySynonym of quartarius, quarter-sextarius, a Roman unit of liquid measure equivalent to about 0.14 L
- quartationThe act, process, or result (in the process of parting) of alloying a button of nearly pure gold with enough silver to reduce the fineness so as to allow acids to attack and remove all metals except the gold.
- quartineA supposed fourth integument of an ovule, counting from the outside.
- quasquicentennialRelating to a period of 125 years.