Duration
Part of speech: noun
Definition: An amount of time or a particular time interval (in the singular, not followed by "of") The time taken for the current situation to end, especially the current war A measure of the sensitivity of the price of a financial asset to changes in interest rates, computed for a simple bond as a weighted average of the maturities of the interest and principal payments associated with it.
Example sentence: Nevertheless, China was unfortunately unable to understand Japan's real position, and it is greatly to be regretted that the Sino-Japanese War became one of long duration.
Length
Part of speech: noun
Definition: The measurement of distance along the longest dimension of an object.durationThe length of a horse, used to indicate the distance between horses at the end of a race.Distance between the two ends of a line segment.The distance down the pitch that the ball bounces on its way to the batsman.total extentpart of something that's long, a physical piece of something
Example sentence: We praise a man who feels angry on the right grounds and against the right persons and also in the right manner at the right moment and for the right length of time.