A person who hallucinates or experiences hallucinations.
From hallucinate with the agentive suffix -or (meaning 'one who does'), following the pattern of English nouns for people who perform actions.
A hallucinator isn't necessarily mentally ill—people with high fevers, sleep deprivation, or on certain medications can hallucinate temporarily, showing that hallucinations are a feature of human neurology that can happen to anyone under the right conditions.
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