AI Search Glossary
The terms you will hear in GEO and AEO conversations, defined in plain English.
The short answer
GEO is generative engine optimization, AEO is answer engine optimization, and AIO here means Google AI Overviews and AI Mode. A citation links to a source in an AI answer, and a mention only names the brand. Below are 20 terms with short definitions.
Last updated November 14, 2026 · Written by the Inspire Clicks senior team
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20 terms, A to Z of AI search
| Term | Definition |
|---|---|
| GEO (generative engine optimization) | Making a brand easy for AI assistants to understand, trust and cite in generated answers. |
| AEO (answer engine optimization) | Structuring pages so search and AI systems can extract a direct answer, such as a definition, steps or a comparison table. |
| AIO (AI Overviews) | Google's AI-generated summaries at the top of some search results. In this site's usage, it includes AI Mode. |
| AI Mode | Google's conversational search experience that can break a question into several related searches. |
| LLM (large language model) | The type of AI model behind assistants such as ChatGPT, Claude and Gemini. |
| Citation | A link or attribution to a specific source inside an AI answer. |
| Mention | When an AI answer names your brand, with or without a link. |
| Query fan-out | When an AI system issues several related searches for one question and combines the results. |
| Entity | A uniquely identifiable thing, such as a company, person, product or place, that search and AI systems try to recognize consistently. |
| E-E-A-T | Experience, expertise, authoritativeness and trustworthiness: quality signals described in Google's guidance for evaluating content. |
| RAG (retrieval-augmented generation) | A method where an AI system retrieves documents and uses them to ground its answer. |
| Grounding | Tying an AI answer to retrieved sources, to reduce made-up statements. |
| Hallucination | An AI statement that sounds plausible but is false or unsupported. |
| Zero-click search | A search that ends without a click to any website. |
| Share of voice | The share of tracked prompts or answers in which your brand appears, compared with competitors. |
| Structured data (JSON-LD) | Machine-readable markup that describes a page and the entities on it. |
| llms.txt | A proposed plain-text file that summarizes a site for AI systems. Optional and unproven; Google says it is not needed. |
| OAI-SearchBot | OpenAI's crawler used to surface sites in ChatGPT search results. |
| GPTBot | OpenAI's crawler used for model training, separate from search. |
| GEO Score | Inspire Clicks' diagnostic model: AI citability 25%, brand authority 20%, content E-E-A-T 20%, technical GEO 15%, schema 10%, platform presence 10%. |
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Keep exploring
- AI Search services →AEO, GEO, AIO and LLM citations as services from Inspire Clicks.
- GEO: executive guide →Why generative engine optimization matters and how it is measured.
- AEO: executive guide →Become the quoted answer, not just the link.
- Google AI Overviews and AI Mode →What Google documents, what the data shows and what to do.
- How-to guides →Step-by-step guides for GEO, AEO, AI Overviews and citations.
- AI visibility FAQ →Straight answers on risk, timelines and measurement.