schizoid personality disorder, a personality disorder characterized by a defect in the ability to form interpersonal relationships, as shown by emotional coldness and aloofness, withdrawn and seclusive behavior, and indifference to praise, criticism, and the feelings of others. The person is unable to express hostility and ordinary aggressive feelings and reacts to disturbing experiences with apparent detachment. The person neither desires nor enjoys personal relationships, prefers solitary activities, and has no close friends or confidants.
