Hallucination: meaning, definitions and examples

A hallucination is when someone perceives something that isn't there, often due to factors like illness, drugs, or lack of sleep.

• He began having hallucinations after being deprived of sleep for three days
• The vivid hallucinations made her see people who weren't actually there

An illusion is a misleading or false visual perception or interpretation of reality. Unlike hallucinations, illusions are often based on real stimuli.

• The magician created an illusion that made it look like the rabbit disappeared
• The straight road ahead looked bent due to the heat creating a mirage, which is an optical illusion

A delusion is a strongly held belief that is false and not based in reality, often found in mental illnesses such as schizophrenia.

• Despite all evidence, he held the delusion that he was a famous historical figure
• Her delusion made her refuse to believe that her family was trying to help her

A phantasm refers to something imagined or dreamlike, often linked to ghosts, apparitions, or supernatural visions.

• He claimed to see a phantasm that resembled his late mother
• The haunted house was said to be filled with phantasms appearing at night