1. a condition in which two distinct, unrelated mental states coexist within the same person. This may occur, for example, in an individual with a dissociative identity disorder. Also called dual consciousness.

2. a condition described by U.S. educator, scholar, and activist W. E. B. Du Bois (1868–1963) as one in which African Americans experience themselves through their own consciousness as well as through their awareness of how they are perceived by White Americans.