GEO glossary

Plain-English definitions of the terms that matter for generative engine optimization (GEO), answer engine optimization (AEO), and AI search visibility in 2026.

• AI Search

  AI search is the umbrella term for search experiences where a generative AI model synthesizes a single answer from many sources, rather than returning a ranked list of links.

• AI Snippet

  An AI snippet is a short, citation-friendly content block — often 1–3 sentences with concrete claims — that AI surfaces lift verbatim into their answers.

• Answer Engine Optimization (AEO)

  Answer Engine Optimization (AEO) is the discipline of getting your content selected as the direct answer in answer engines like ChatGPT, Perplexity, Google AI Overviews, and Bing Copilot.

• Bing Copilot

  Bing Copilot is Microsoft's AI assistant integrated into Bing Search, powered by GPT-4 class models and the Bing retrieval index.

• Brand Recall (LLM)

  Brand recall in LLMs is the unprompted likelihood that a large language model names your brand when answering a relevant category question.

• ChatGPT Search

  ChatGPT Search is OpenAI's integrated search feature inside ChatGPT, which performs live web retrieval and combines it with the underlying GPT model's parametric knowledge.

• Citation Rate

  Citation rate is the percentage of AI answers that link to your domain as a source.

• Claude Search

  Claude Search is Anthropic's integrated web search feature inside Claude, which performs live retrieval and synthesizes cited answers.

• E-E-A-T for AI

  E-E-A-T for AI is the application of Google's Experience, Expertise, Authoritativeness, and Trustworthiness framework to content optimized for AI search surfaces.

• Gemini Deep Research

  Gemini Deep Research is Google's long-form AI research feature, producing multi-page synthesized reports on a topic with citations to many sources.

• Generative Engine Optimization (GEO)

  Generative Engine Optimization (GEO) is the practice of getting a brand named or cited in AI-generated answers from ChatGPT, Claude, Perplexity, and Gemini.

• Google AI Overviews

  Google AI Overviews is the AI-generated answer panel that appears above traditional Google search results for many queries, synthesizing information from top-ranked sources.

• LLM Citations

  LLM citations are the source links or attributions that large language models include in their generated answers.

• LLM Ingestion

  LLM ingestion is the process by which large language models incorporate your content into their training data and retrieval-augmented answers.

• Mention Rate

  Mention rate is the percentage of relevant AI-generated answers in which your brand name appears.

• Model Knowledge Cutoff

  A model's knowledge cutoff is the date after which the language model has no information in its training data.

• Perplexity Pages

  Perplexity Pages is Perplexity's feature for generating shareable, citation-rich research pages on a given topic.

• Prompt Universe

  A prompt universe is the defined set of questions you sample against AI surfaces to measure your brand's visibility — typically 100–500 prompts covering awareness, consideration, and decision-stage buyer queries.

• Retrieval-Augmented Generation (RAG)

  Retrieval-augmented generation (RAG) is the architecture in which a language model fetches relevant documents at query time and incorporates them into its generated answer.

• Share of Voice (AI)

  Share of voice in AI search is your brand's mention rate relative to direct competitors in the same prompt set across AI assistants.