In Freudian theory, the division of the psyche that is totally unconscious and serves as the source of instinctual impulses and demands for immediate satisfaction of primitive needs.
The mass of primitive instincts and energies in the unconscious mind that, modified by the ego and the superego, underlies all psychic activity
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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