<p><strong>Adjective</strong></p><ul><li>Of, relating to, or belonging as a part of the whole; constituent or component: integral parts.</li><li>Necessary to the completeness of the whole: This point is integral to his plan.</li><li>Synonyms: requisite, indispensable, essential.</li><li>Consisting or composed of parts that together constitute a whole: entire, complete, whole: the integral works of a writer.</li><li>Arithmetic: pertaining to or being an integer; not fractional.</li><li>Mathematics: pertaining to or involving integrals.</li></ul><p><strong>Noun</strong></p><ul><li>An integral whole.</li><li>Mathematics: Also called Riemann integral. The numerical measure of the area bounded above by the graph of a given function, below by the x-axis, and on the sides by ordinates drawn at the endpoints of a specified interval; the limit, as the norm of partitions of the given interval approaches zero, of the sum of the products of the function evaluated at a point in each subinterval times the length of the subinterval.</li><li>A primitive.</li><li>Any of several analogous quantities.</li></ul>