(1) Act or process of determining classification or nature of. (2) A sense of oneness, or psychic continuity with another person or group; one of the freudian defense mechanisms common to everyone, whereby anxiety regarding one's personal identity or worth is dissipated through the mechanism of perceiving oneself as having characteristics in common with a person in the public eye, or in childhood identifying with a more powerful person such as a parent. SYN: incorporation. [Mediev. L. identicus, fr. L. idem, the same, + facio, to make]