Psychiatry. a mental disorder characterized by systematized delusions and the projection of personal conflicts, which are ascribed to the supposed hostility of others, sometimes progressing to disturbances of consciousness and aggressive acts believed to be performed in self-defense or as a mission.
baseless or excessive suspicion of the motives of others.
a form of schizophrenia characterized by a slowly progressive deterioration of the personality, involving delusions and often hallucinations
a mental disorder characterized by any of several types of delusions, in which the personality otherwise remains relatively intact
(informal) intense fear or suspicion, esp when unfounded