n. the god of love in Greek mythology (equivalent to the Roman Cupid), whose name was chosen by Sigmund Freud to designate a theoretical set of strivings oriented toward sexuality, development, and increased life activity (see life instinct). In Freud’s dual instinct theory, Eros is seen as involved in a dialectic process with Thanatos, the striving toward reduced psychical tension and life activity (see death instinct). See also libido.