1. an obsessive preoccupation with a single idea, impulse, or aim, as in an idée fixe.

2. a shortened name for visual fixation.

3. in psychoanalytic theory, the persistence of an early stage of psychosexual development or the inappropriate attachment to an early psychosexual object or mode of gratification, such as anal or oral activity; this fixation limits the person’s ability to negotiate the tasks of later psychosexual stages. —fixate vb.