having false or unrealistic beliefs or opinions: Senators who think they will get agreement on a comprehensive tax bill are delusional.
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.

Nearby words

  1. deluge,
  2. delusion,
  3. delusion of grandeur,
  4. delusion of negation,
  5. delusion of persecution,
  6. delusive,
  7. delusively,
  8. delusory,
  9. delusterant,
  10. delustering

Sometimes de·lu·sion·ar·y. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for delusional

Word Origin and History for delusional



1871, from delusion + -al (1).

Online Etymology Dictionary, © 2010 Douglas Harper