Advanced – AI & ML Testing
Hallucination – ISTQB Definition
Last Updated: July 12, 2026 · SoftwareTestPilot QA Team
Official ISTQB Definition
An AI model output that is fluent and confident but factually incorrect or unsupported by input data.
In simple words
When the AI makes stuff up but sounds sure about it.
Exam tip
Hallucination is measured with grounding checks, citation verification, and reference datasets.
Related terms
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