integral āļāļ·āļāļāļ°āđāļĢ integral āļāļ·āļāļāļ°āđāļĢ Essential or necessary for completeness; constituent: The kitchen is an integral part of a house. Possessing everything essential; entire.Mathematics Expressed or expressible as or in terms of integers. Mathematics Expressed as or involving integrals.A complete unit; a whole.Mathematics A number computed by a limiting process in which the domain of a function, often an interval or planar region, is divided into arbitrarily small units, the value of the function at a point in each unit is multiplied by the linear or areal measurement of that unit, and all such products are summed.Mathematics A definite integral.Mathematics An indefinite integral.