AI & Technology

What Is an AI Hallucination?

An AI hallucination is output from an AI model that sounds confident and plausible but is false, unsupported, or made up — such as an invented fact, statistic, quote, or source. It happens because language models generate likely-sounding text rather than retrieving verified facts by default.

Why It Happens

Models predict the next token based on patterns in their training data. When the data is missing, ambiguous, or outdated, the most plausible continuation may simply be wrong.

How It Is Reduced

Grounding answers in provided documents (retrieval-augmented generation), asking for sources, and checking important facts against reliable references all reduce the risk.

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🔗 Related Terms

Large Language Model (LLM) Retrieval-Augmented Generation (RAG) Training Data AI Bias

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Last updated: September 29, 2026. This definition is for general educational purposes only. It is not financial, investment, tax, legal, or medical advice, and it does not recommend any product or course of action. For decisions about your own situation, consult a qualified professional.