The GEO Glossary

The language of AI answers, defined.

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24 terms

A

AI crawlerAn AI crawler is a bot that fetches web pages for an AI system, either to build training data, to power live answer retrieval, or to fetch a page a user asked about.AI visibilityAI visibility is how often, how prominently, and how accurately a brand appears in the answers AI models give to relevant questions.AI visibility scoreAn AI visibility score is a single number summarizing how visible a brand is in AI answers, blending presence measures such as mention rate with authority measures such as citations.Answer engineAn answer engine is a system that responds to a question with a composed answer rather than a list of links: ChatGPT, Claude, Gemini, Perplexity, Copilot, and AI-augmented search results all behave as answer engines.Answer Engine Optimization (AEO)Answer engine optimization (AEO) is the practice of making a brand present, accurate, and preferred in the composed answers of AI systems such as ChatGPT, Claude, Gemini, and Perplexity.Answer-first blockAn answer-first block is a passage that states its direct answer in the opening sentence or two, before context or qualification, so an AI system can lift it whole as a self-contained quote.Authority citationAn authority citation is a source cited in an AI answer that is a recognized independent authority, such as an industry publication, review platform, or news outlet, and that references the brand.

B

Brand factsBrand facts are the concrete, checkable claims AI models make about a brand: pricing, features, locations, founding details, integrations.Branded promptA branded prompt is a question that names the brand directly, such as "is Acme legit" or "Acme pricing".

C

Citation rateCitation rate is the fraction of AI answers that cite a brand’s own website as a source, out of all answers collected for its tracked questions.Competitor promptA competitor prompt is a comparison question that puts brands side by side, such as "Acme vs Initech" or "alternatives to Initech".Consensus gateA consensus gate is a ranking rule that requires a brand to be named independently by at least two different AI engines before it can be ranked at all.Coverage illusionThe coverage illusion is the false confidence produced by measuring AI visibility on only one or two engines: the numbers look complete and stable, but the unmeasured engines frequently disagree, so the picture is wrong in ways the tracker cannot see.

D

Discovery promptA discovery prompt is a question a buyer asks when they do not yet know which brands exist, such as "best accounting software for a small business".

E

Engine disagreementEngine disagreement is the extent to which different AI engines give different answers to the same question: naming different brands, ranking them differently, or contradicting each other on facts.

F

Frozen editionA frozen edition is an immutable, dated snapshot of an AI visibility ranking together with the complete evidence behind it: every verbatim answer, every extracted brand, and the method used.

G

Generative Engine Optimization (GEO)Generative Engine Optimization (GEO) is the practice of improving how AI models describe and recommend a brand: making the brand present, accurate, and preferred in generated answers.

H

Hallucination (brand context)A hallucination is a confident AI statement with no basis in any source: an invented feature, a fabricated statistic, a product that does not exist.

L

LLMO (Large Language Model Optimization)LLMO, short for large language model optimization, is the practice of improving how large language models describe and recommend a brand in their answers.llms.txtllms.txt is a proposed convention: a plain-text file at the root of a website that gives AI systems a concise, structured summary of what the site is and where its important content lives, the way robots.txt addresses crawlers.

M

Mention rateMention rate is the fraction of AI answers that name a brand at least once, out of all answers collected for its tracked questions.

P

Prompt battleA prompt battle is the head-to-head contest inside a single buying question: for one prompt, which brands did the AI models name, in what order, and who won.

R

Regional divergenceRegional divergence is the difference between AI answers to the same question asked from different countries: the same category can have different leaders, or an entirely different shortlist, in the US, UK, Australia, and Canada.

S

Share of voice in AI answersShare of voice in AI answers is the percentage of brand mentions across a set of AI responses that belong to one brand.

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