: mental illness characterized by systematized delusions of persecution or grandeur usually without hallucinations
- Psychotic symptoms and paranoia persisted, and she continued to "find clues" of conspiracy against her.
- —Helen K. Delichatsios et al.
: a tendency on the part of an individual or group toward excessive or irrational suspiciousness and distrustfulness of others
- The members of America's racist right inhabit a murky world of conspiracy, suspicion, and paranoia.
- —Wayne King
\ˌper-ə-ˈnȯi-ˌak, -ˈnȯi-ik, ˌpa-rə-\
or less commonly
\ˌper-ə-ˈnȯi(-i)k, -ˈnō-ik, ˌpa-rə-\ adjective or noun
\ˌper-ə-ˈnȯi(-i)-k(ə-)lē, -ˈnō-i-k(ə-)lē, ˌpa-rə-\