[ dih-loo-zhuh-nl ]
See synonyms for delusional on
  1. having false or unrealistic beliefs or opinions: Senators who think they will get agreement on a comprehensive tax bill are delusional.

  2. Psychiatry. maintaining fixed false beliefs even when confronted with facts, usually as a result of mental illness: He was so delusional and paranoid that he thought everybody was conspiring against him.

Origin of delusional

First recorded in 1850–60; delusion + -al1
  • Sometimes de·lu·sion·ar·y . Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023