Psychotic behavior accompanied by persecutory or grandiose delusions with few other signs of personality or thought disturbance.

Paranoia is an instinct or thought process that is believed to be heavily influenced by anxiety, suspicion, or fear, often to the point of delusion and irrationality. Paranoid thinking typically includes persecutory beliefs, or beliefs of conspiracy concerning a perceived threat towards oneself (e.g., "Everyone is out to get me")...