Definition

Adjective: 1. Suffering from dementia; insane; mad: Describes a person whose mental faculties are severely impaired, often due to illness or extreme emotion, resulting in irrational or wildly foolish behavior. 2. Wildly foolish or irrational: Can describe actions, ideas, or states that are so illogical or absurd as to seem insane.

Usage

• Used to describe a person's state of mind, typically implying a severe and often distressing loss of rationality.
• Can be used informally and hyperbolically to describe extreme foolishness or chaos, not necessarily clinical insanity.
• Often carries a stronger, more dramatic connotation than words like "crazy" or "foolish."

Examples

• Adjective:
  • The demented patient required constant care. (Describes a person with a medical condition).
  • He was demented with grief after the loss. (Describes a temporary state of extreme, irrational emotion).
  • Their plan to build a house of cards in a windstorm was utterly demented. (Describes a wildly foolish idea).

Advanced Usage

• "To drive someone demented": To irritate, annoy, or frustrate someone to an extreme degree.
  • The constant noise from the construction site is driving me demented.

Variants and Related Words

• Dementia (n): The medical condition of chronic or persistent disorder of mental processes, marked by memory disorders, personality changes, and impaired reasoning.
  • The doctor diagnosed the patient with advanced dementia.
• Dement (v, archaic): To make insane or to drive mad. (Rarely used in modern English).
  • The horrific sights were enough to dement a person.

Synonyms

• Insane: Of unsound mind; clinically mad.
• Mad: Mentally ill; insane. (Also used informally for anger or excitement).
• Deranged: Disturbed the orderly arrangement of; unsettled the mind of.
• Unhinged: Mentally unbalanced; disturbed.
• Lunatic: (Informal, potentially offensive) Wildly foolish or insane.

Antonyms

• Sane: Of sound mind; not mad or mentally ill.
• Rational: Based on or in accordance with reason or logic.
• Lucid: Expressed clearly; easy to understand. (Also: able to think clearly, especially in intervals between periods of confusion).

Related Idioms

• (As) mad as a hatter: Completely insane. (This idiom is closely related in meaning to "demented" in its informal sense).
  • He was running around shouting at pigeons—he was as mad as a hatter.

Adjective

1. affected with madness or insanity
   • a man who had gone mad