Breadcrumb Home > Dictionary > Index B bipolar disorder: Meaning and Definition of Find definitions for: bipo'lar disor'der Pronunciation: [key] — Psychiatry. Psychiatry. an affective disorder characterized by periods of mania alternating with periods of depression, usually interspersed with relatively long intervals of normal mood. Formerly, Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. bipolar bippy ✖ Related Content Daily Word Quiz: ultimathule Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language