A hallucination is a perception in the absence of a stimulus.

Hallucination or Hallucinations may also refer to:

• "Hallucination" (short story), a 1985 science fiction short story by Isaac Asimov
• Hallucinations (short story), a 1997 science fiction horror short story by Junji Ito
• Hallucinations (book), a 2012 book by Oliver Sacks

• Hallucination (artificial intelligence), assertion by an AI that is unjustified by its training data

• Alcoholic hallucinosis
• Hallucinogen, a large and diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception

• Hallucination Recordings, a record label
• Hallucinations (Atrocity album) (1990)
• Hallucinations (David Usher album) (2003)
• Hallucinations (EP), a 2019 EP by Pvris
• Hallucination (song), a song by Regard and Years & Years
• Hallucinations: Psychedelic Pop Nuggets from the WEA Vaults, a 2004 compilation album
• "Hallucinations", a 2009 single by Angels & Airwaves from Love
• "Hallucinations", a bebop-era composition by Bud Powell covered by many jazz musicians
• The Halluci Nation, a Canadian electronic music group formerly known as A Tribe Called Red

• All pages with titles beginning with Hallucination
• All pages with titles containing Hallucination