n.1 a mental disorder esp. characterized by delusions of persecution and self-importance.
2 an abnormal tendency to suspect and mistrust others.
Derivatives:
paranoiac adj. & n. paranoiacally adv. paranoic adj. paranoically adv. paranoid adj. & n.
Etymology: mod.L f. Gk f. paranoos distracted (as PARA-(1), noos mind)