The definition of an interval is a space or a period of time between things.(noun)
An example of an interval is a 15-minute gap between train arrivals.
See interval in Webster's New World College Dictionary
Origin: ME enterval, intervalle < OFr < L intervallum, lit., space between two palisades or walls < inter-, between + vallum, palisade, wall
See interval in American Heritage Dictionary 4
Origin: Middle English intervalle
Origin: , from Old French
Origin: , from Latin intervallum
Origin: : inter-, inter-
Origin: + vallum, rampart.
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