PARANOIA
paranoia
(noun) a psychological disorder characterized by delusions of persecution or grandeur
Source: WordNet® 3.1
Etymology
Noun
paranoia (countable and uncountable, plural paranoias)
A psychotic disorder characterized by delusions of persecution, conspiracy and perceived threat against the person, often associated with false accusations and general mistrust of others
Antonym: pronoia
Extreme, irrational distrust of others.
Source: Wiktionary
Par`a*noi"a, n. Etym: [NL., fr. Gr. (Med.)
Definition: Mental derangement; insanity.
Source: Webster’s Unabridged Dictionary 1913 Edition