delusional

Meanings

1. 1adjectivenot comparablemedical

   Holding false beliefs firmly despite clear evidence, especially as part of a mental condition.

   Grammar: Usually predicative or before a noun; stronger and more clinical than simply “mistaken.”

   Patterns

   • delusional belief
   • become delusional
   • delusional thinking

   The patient became delusional and believed strangers were following him.

   A delusional belief may remain fixed even after the facts are explained.

   Stress and lack of sleep can sometimes make people mildly delusional.

2. 2adjectivecomparableinformaldisapproving

   Unrealistically confident or hopeful about something unlikely to happen.

   Grammar: Informal use; can take “more” or “most,” and is often disapproving.

   Patterns

   • delusional to think
   • completely delusional
   • delusional about something

   Thinking you can learn the whole course in one night is delusional.

   He was delusional about his chances of winning the lottery.

   Calling the plan realistic when the budget is missing is simply delusional.

Common combinations

delusional belief

The doctor asked whether the delusional belief had lasted more than a week.

delusional thinking

Lack of sleep can feed delusional thinking during a crisis.

delusional about chances

Fans were delusional about their team’s chances after three losses.

completely delusional

Expecting everyone to agree with you is completely delusional.

Synonyms and how they differ

unrealistic

Unrealistic is milder and can describe plans; delusional suggests false belief or extreme overconfidence.

misguided

Misguided means based on poor judgment, but not necessarily a fixed false belief.

paranoid

Paranoid involves fear of harm or persecution; delusional may involve many kinds of false beliefs.

Opposites

Word family

delusion noun

A false belief held despite evidence.

delude verb

To make someone believe something false.

deluded adjective

Deceived or holding a mistaken belief; often less clinical than delusional.

Commonly confused: delusional or illusional?

Practice

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