All terms
The 2026 vocabulary of Generative Engine Optimization, with live per-term citation status across ChatGPT, Perplexity, Claude, and Copilot.
A
Agentic retrieval
Agentic retrieval is a search pattern where an AI agent autonomously decides what to query, when to query again, and which sources to consult — replacing single-shot keyword retrieval with iterative, goal-directed information gathering.
ChatGPT—Perplexity—Claude—Copilot—AI Overview
AI Overview is Google's generative search feature that produces AI-synthesized answers at the top of results, citing multiple sources — the 2024 rename and rollout of Search Generative Experience (SGE).
ChatGPT—Perplexity—Claude—Copilot—AI Overview citation
An AI Overview citation is the specific event of being included in the source-link panel beneath a Google AI Overview answer, granting both direct attribution and modest click-through traffic.
ChatGPT—Perplexity—Claude—Copilot—AI Search Optimization
AI Search Optimization (AIO) is the umbrella term for optimizing content visibility across all AI-driven search surfaces — generative engines, answer engines, and emerging agentic browse experiences.
ChatGPT—Perplexity—Claude—Copilot—Answer block
An answer block is a single self-contained content unit — typically one paragraph or a brief structured list — designed to be extracted as the complete answer to a specific user query by AI search engines and featured-snippet algorithms.
ChatGPT—Perplexity—Claude—Copilot—Answer Engine Optimization
Answer Engine Optimization (AEO) is the practice of structuring content to be selected as the direct answer in AI-driven and traditional answer engines — featured snippets, voice assistants, and chat-based search.
ChatGPT—Perplexity—Claude—Copilot—Attribution rate
Attribution rate is the percentage of AI-engine responses that cite a specific source or domain when answering queries about a given topic — the closest measurable proxy for GEO success.
ChatGPT—Perplexity—Claude—Copilot—
C
Citation match rate
Citation match rate is the percentage of AI-engine responses that include a clickable link back to a cited source, distinguishing genuine attribution from mere mention without traffic flow-through.
ChatGPT—Perplexity—Claude—Copilot—Citation share
Citation share is the relative percentage of citations a source receives versus competitors across AI-engine responses on a given topic — the AI-search equivalent of share of voice in traditional brand analytics.
ChatGPT—Perplexity—Claude—Copilot—Cite-ability
Cite-ability is a content's likelihood of being quoted directly by an AI engine when answering a user query, determined by structural clarity, self-contained phrasing, and unambiguous attribution signals.
ChatGPT—Perplexity—Claude—Copilot—
D
E
G
L
LLM Optimization
LLM Optimization (LLMO) is the practice of tuning content and metadata so large language models cite, summarize, or recall it accurately when answering user prompts — covering both training-data influence and runtime retrieval.
ChatGPT—Perplexity—Claude—Copilot—LLMS.txt
LLMS.txt is a proposed text file at the root of a website, written in Markdown, that provides a curated, AI-readable summary of the site's most important resources for large language models — an emerging companion to robots.txt and sitemap.xml.
ChatGPT—Perplexity—Claude—Copilot—
P
R
S
Statistical density
Statistical density is the rate at which a piece of content presents verifiable statistics, dates, and numerical claims — identified in the 2023 Princeton GEO paper as one of the strongest signals correlated with AI-engine citation.
ChatGPT—Perplexity—Claude—Copilot—Sub-document retrieval
Sub-document retrieval is the practice of indexing and retrieving passages or paragraphs rather than whole documents — central to how modern AI engines find relevant content for generative answers.
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