Толковый словарь английского языка Oxford English Reference - duration

n. 1 the length of time for which something continues. 2 a specified length of time (after the duration of a minute). Phrases and idioms for the duration 1 until the end of the war. 2 for a very long time. Derivatives durational adj. Etymology: ME f. OF f. med.L duratio -onis (as DURANCE)