delusional

[ dih-loo-zhuh-nl ]

adjective

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.

Word History and Origins

Origin of delusional¹

First recorded in 1850–60; delusion ( def ) + -al ¹( def )

Example Sentences

These people are clearly delusional, or think they’re invincible.

From Essence.com

When you hear that someone is delusional, you might think they’re schizophrenic or psychotic.

From Science News

Today both the Senate and House will vote multiple times to reject your delusional conspiracy theories and affirm the certified Electoral College results.

From Fortune

If someone told you in March, when the World Health Organization finally called the Covid-19 outbreak a pandemic, that we’d have three strong coronavirus vaccine candidates by mid-November, you might have called that person delusional.

From Vox

It doesn’t necessarily mean that those who score very high in the Light Triad are delusional.

From Nautilus

At one point they even told her she was delusional, despite her diffuse ulcerating lesions.

From The Daily Beast

I suppose you can if you were dumb and delusional enough to think that the Emmy voters might liven things up a little bit.

From The Daily Beast

He became acutely delusional and committed suicide after attacking his father.

From The Daily Beast

But according expert opinion and the case details released to the public, she was also floridly psychotic and delusional.

From The Daily Beast

Burke insists that he is not nostalgic and he is not delusional.

From The Daily Beast

Paranoia, as it is called, mild delusional insanity, may assert itself and then may persist for the rest of life.

From Project Gutenberg

Later we shall have something to say about the delusional systems which appear to be common to the crowd-mind and the paranoiac.

From Project Gutenberg

May, 1907:—Still delusional, hypochondriacal; paralysis very much improved.

From Project Gutenberg

On his transfer to our Hospital he readily carries  over his delusional ideas to the officials here.

From Project Gutenberg

He adhered very tenaciously to his delusional system and believed himself fully justified in all his litigious pursuits.

From Project Gutenberg

Related Words

• unrealistic