hallucinate
verb
hal·lu·ci·nate
hə-ˈlü-sə-ˌnāt 
hallucinated; hallucinating
1
: to affect with visions or imaginary perceptions
2
: to perceive or experience as a hallucination
: to have hallucinations
Examples of hallucinate in a Sentence
The patient may hallucinate if she has a fever.
Recent Examples on the Web
For example, OpenAI’s 03 and 04-mini models hallucinate—that is, makes up its own answers to questions—around 30 to 50% of the time, per the company’s own recent tests.
—
Victoria Feng, Forbes.com, 15 July 2025
Did Martin’s outburst finally convince Masha that hallucinating the ghosts of your past isn’t the healthiest way to deal with loss?
—Rafaela Bassili, Vulture, 2 July 2025
When LLMs hallucinate, the consequences can be spectacular.
—Gabriel Snyder, MSNBC Newsweek, 25 June 2025
Once Player 96 is knocked off the bridge by the rope, other players — including Min-su, who is hallucinating after taking his last pill — are able to cross.
—Jennifer Zhan, Vulture, 27 June 2025
See All Example Sentences for hallucinate
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Victoria Feng, Forbes.com, 15 July 2025
Did Martin’s outburst finally convince Masha that hallucinating the ghosts of your past isn’t the healthiest way to deal with loss?
—Rafaela Bassili, Vulture, 2 July 2025
When LLMs hallucinate, the consequences can be spectacular.
—Gabriel Snyder, MSNBC Newsweek, 25 June 2025
Once Player 96 is knocked off the bridge by the rope, other players — including Min-su, who is hallucinating after taking his last pill — are able to cross.
—Jennifer Zhan, Vulture, 27 June 2025
See All Example Sentences for hallucinate
Cite this Entry
“Hallucinate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hallucinate. Accessed 21 Jul. 2025.
Copy CitationKids Definition
hallucinate
verb
hal·lu·ci·nate
hə-ˈlüs-ə-ˌnāt
hallucinated; hallucinating
: to have hallucinations or experience as a hallucination
Medical Definition
hallucinate
verb
hal·lu·ci·nate
hə-ˈlüs-ᵊn-ˌāt
hallucinated; hallucinating
1
: to affect with visions or imaginary perceptions
the patient is not hallucinated
2
: to perceive or experience as a hallucination
may hallucinate monsters or attackers—M. J. Horowitz
M. J. Horowitz
: to have hallucinations
Love words? Need even more definitions?
Merriam-Webster unabridged
Share