The definition of integral is anything that is necessary in order for something to be completed.(adjective)
An example of integral is the study of basic math in an elementary school curriculum.
See integral in Webster's New World College Dictionary
Origin: LL integralis < L integer: see integer
See integral in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Medieval Latin integrālis, making up a whole
Origin: , from Latin integer, complete; see integer.
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