AEO & GEO glossary
The vocabulary of AI search, in plain language. Each term is a short, direct definition of how it works and why it matters for your brand's visibility in AI answers.
Answer Engine
An answer engine is a system like ChatGPT, Perplexity, or Google AI Overviews that returns a direct, synthesized answer instead of a list of links.
Share of Voice (AI)
Share of voice in AI search is the percentage of relevant prompts where an AI engine mentions your brand, compared to your competitors.
Citation Rate
Citation rate is how often an AI engine links to or references your website as a source when it answers questions in your category.
AI Crawler
An AI crawler is a bot, such as GPTBot, ClaudeBot, or PerplexityBot, that fetches web pages so AI engines can use them in training or live answers.
llms.txt
llms.txt is a proposed plain-text file at a site's root that gives AI models a clean, structured summary of the site's key content.
Entity Recognition
Entity recognition is how AI systems identify and connect a brand, product, or person as a distinct entity rather than a loose string of words.
Zero-Click Search
A zero-click search is a query answered directly on the results page or by an AI engine, so the user never clicks through to a website.
AI Overviews
AI Overviews are Google's AI-generated summaries that appear above traditional search results and cite a handful of sources.
Retrieval-Augmented Generation (RAG)
RAG is a technique where an AI model retrieves relevant documents at answer time and uses them to ground its response.
Prompt Volume
Prompt volume is an estimate of how often people ask AI engines a particular question or type of question.
Brand Sentiment (AI)
Brand sentiment in AI search is whether an engine describes your brand positively, neutrally, or negatively when it mentions you.
Source Gap
A source gap is a topic or query where AI engines cite your competitors' sources but not yours.
Fan-Out Queries
Fan-out is when an AI engine breaks one user question into several sub-queries, retrieves sources for each, then combines them into one answer.
AI Referral Traffic
AI referral traffic is the website visits that come from users clicking a citation or link inside an AI answer.
Grounding
Grounding is tying an AI model's answer to verifiable external sources rather than only its internal training.
Hallucination
A hallucination is when an AI engine states something false or invented, including incorrect claims about a brand.