Free reference · Schema-first · Solo-built
Every term in AI search, defined and citation-tracked.
Plain-English definitions of GEO, AEO, AIO, LLMO, DefinedTerm schema, sub-document retrieval, and the rest of the 2026 AI-search vocabulary. Each entry is paired with live data on whether ChatGPT, Perplexity, Claude, and Copilot actually cite it.
- Terms shipped
- 90
- With AI citation
- 39
- Engines tracked
- 5
Why this exists
AI search engines cite content with proper schema markup. But the vocabulary itself (what GEO actually means, how it differs from AEO, which schema types AI Overview prefers) has been scattered across SEO blogs, Twitter threads, and outdated vendor definitions.
GEO Glossary is the canonical reference: every term shipped as a DefinedTerm JSON-LD record, hand-edited, with a per-engine citation tracker updated weekly. No popups. No lead-magnet gates. No ads.
Frequently asked questions
- What is Generative Engine Optimization (GEO)?
- Generative Engine Optimization (GEO) is the practice of writing, structuring, and signalling content so AI search engines (ChatGPT, Perplexity, Claude, Copilot, Gemini, Google AI Overview) cite it in their generated answers. It overlaps with traditional SEO at the content-quality layer but diverges on retrieval, schema markup, and per-engine citation behaviour.
- How is GEO different from SEO, AEO, AIO, and LLMO?
- SEO optimizes for ranked links on a search results page. GEO, AEO (answer engine optimization), AIO (AI search optimization), and LLMO (LLM optimization) overlap heavily and are often used interchangeably; GEO is the most widely adopted umbrella term in 2026 for optimizing content so AI engines include and cite it inside generated answers. See the per-term entries on this site for the operational distinctions.
- What is cite-ability and how do I measure it?
- Cite-ability is a practitioner-coined content property describing how suitable a passage is for AI extraction, quotation, and attribution. There is no standardized scoring tool; the operational proxy is to query AI engines with related questions and check whether your content is quoted (verbatim or paraphrased) in the response, with attribution. This site tracks cite-ability per engine on every term entry's citation-status badges.
- How is GEO Glossary different from other GEO references?
- GEO Glossary is positioned as an editorial-first, vendor-neutral, indie-maintained terminology reference for AI search, with 60+ entries that systematically split vendor-documented claims from observable engine behaviour from practitioner inference. Each term page displays per-engine citation status (untested / not-cited / cited) updated weekly. Most alternative GEO references on the market are SaaS product-marketing collateral, agency content marketing, or PR-placement authority positioning; this glossary is the product, not a sales funnel. See why this exists for the full positioning.
- How often is each term updated?
- Every term page exposes a frontmatter changelog showing what was revised and when, plus a last-fact-checked date in the footer. Editorial passes run continuously; substantive entries (cluster anchors, contested-topic entries) go through one or more independent LLM peer-review rounds after the initial fact-audit. The full workflow is published at /about/editorial-methodology.
More definitions and the full editorial methodology: all 90 terms · research · about · AI citation metrics pillar.