This AI search glossary defines 42 terms used in AEO, GEO and AI visibility work, from share of voice to GPTBot. Each term opens with a one-sentence definition you can quote on its own, then gives a link to the full guide where one exists and a note where Depra AI does not measure it. To point someone to one term, link to it directly, for example depra.ai/glossary#citation.
AEO and GEO are two names for the same job: getting your brand named and cited when a buyer asks ChatGPT, Gemini, Perplexity, Google AI Overviews or any other major AI engine what to buy. The terms below run from A to Z, and each one also sits in its group: strategy, engines, how answers are built, prompts, metrics, sources and crawlers.
All 42 terms, A to Z
Terms starting with A
- AEO (answer engine optimization)Link to AEO (answer engine optimization)
AEO, short for answer engine optimization, is the work of getting your brand named and cited in the answers that ChatGPT, Gemini, Perplexity, Google AI Overviews and every other major AI engine write for a question.
Full guide: what is AEO.
- AI OverviewLink to AI Overview
An AI Overview is the AI-written summary Google shows above some search results, with links to pages it drew on.
Google does not show one for every search, so Depra AI records whether an Overview appeared as well as whether it named you (Google AI Overview tracker).
- AI SEOLink to AI SEO
AI SEO is a broad label for search work aimed at AI answers, used for both AEO and GEO.
Full guide: what is AI SEO. How it differs from classic search work: GEO vs SEO and AEO vs SEO.
- AI visibilityLink to AI visibility
AI visibility is how often AI names your brand: the share of AI answers to your buyers' questions that mention you.
Depra AI measures it with its AI visibility tracker. Full guide: what is AI visibility.
- Answer languageLink to Answer language
Answer language is the language an AI engine replies in, which can differ from the language of the question.
Depra AI detects the reply language on every answer.
- Average positionLink to Average position
Average position is where your brand comes when an answer lists several options, averaged across answers, where 1 means named first.
Terms starting with B
- Branded vs non-branded promptLink to Branded vs non-branded prompt
A branded prompt contains your brand name and almost always returns it, and a non-branded prompt does not.
Depra AI leaves branded prompts out of your scores by default.
Terms starting with C
- ChatGPT searchLink to ChatGPT search
ChatGPT search is ChatGPT's web search feature, which looks up current pages before it answers and shows the sources it used.
Depra AI captures ChatGPT answers with search switched on (ChatGPT visibility tracker).
- ChatGPT-UserLink to ChatGPT-User
ChatGPT-User is the agent ChatGPT uses when it visits a page because a user asked something.
OpenAI says robots.txt rules may not apply to it (OpenAI crawler docs (opens in a new tab)).
- CitationLink to Citation
A citation is a link to a web page that an AI answer shows as a source.
- Citation gapLink to Citation gap
A citation gap is a website AI cites when it recommends your competitors but never when it names you, which makes it a place to get mentioned.
Depra AI lists these sites in its citation gap analysis.
- Cited sourceLink to Cited source
A cited source is a website AI answers link to.
Depra AI labels each one by type, such as editorial, forum, marketplace, directory, company site or your own site.
- Code-mixed promptsLink to Code-mixed prompts
Code-mixed prompts are buying questions that mix two languages in one sentence, such as Hinglish (Hindi and English typed in English letters).
The same buying question can get different brands in English and in Hinglish (English vs Hinglish study). Depra AI tracks questions in English, Hinglish, French and most other major languages, plus code-mixed questions, on every plan.
- Confidence rangeLink to Confidence range
A confidence range is the band a percentage most likely sits in, given the number of answers behind it.
Your Depra AI report shows a 95% range for visibility.
Terms starting with E
- EntityLink to Entity
An entity is a distinct thing, such as a brand, person or product, that search engines and AI models recognise and link to facts about it.
Depra AI does not audit entity data.
Terms starting with G
- GeminiLink to Gemini
Gemini is Google's AI assistant at gemini.google.com.
Depra AI checks it daily in the same web app people use (Gemini visibility tracker).
- GEO (generative engine optimization)Link to GEO (generative engine optimization)
GEO, short for generative engine optimization, is the work of making your pages the sources AI answers draw on.
It is the same goal as AEO under a name taken from a 2023 research paper. Full guide: what is GEO, and how the terms relate in AEO vs GEO vs SEO.
- Google AI ModeLink to Google AI Mode
Google AI Mode is a separate Google search mode where you ask follow-up questions in a chat and get a longer AI answer with links.
AI Mode is an Enterprise add-on; every plan includes ChatGPT, Gemini, Google AI Overviews and Perplexity.
- Google-ExtendedLink to Google-Extended
Google-Extended is a robots.txt token with no crawler of its own that controls whether Google may use your content to train Gemini models and for grounding.
Google says it does not affect inclusion in Google Search (Google crawler docs (opens in a new tab)).
- GPTBotLink to GPTBot
GPTBot is OpenAI's crawler for content that may be used to train its AI models (OpenAI crawler docs (opens in a new tab)).
- GroundingLink to Grounding
Grounding is tying an AI answer to real sources, such as search results, so the model writes from current pages in place of its memory alone.
Terms starting with H
- HinglishLink to Hinglish
Hinglish is Hindi and English typed together in English letters, the way many Indian buyers write a question.
Depra AI, whose speciality is Hinglish, tracks Hinglish versions of your questions next to English (Hinglish AI visibility), and our English vs Hinglish study shows how the answers differ.
Terms starting with K
- Knowledge cutoffLink to Knowledge cutoff
A knowledge cutoff is the date after which a model has no training data, so without web search it cannot know about newer products, prices or brands.
Terms starting with L
- ListicleLink to Listicle
A listicle is a "best X for Y" list article.
Depra AI labels cited pages as listicles, comparisons, how-tos, product pages and more, so you can see which formats AI cites in your category.
- LLM SEOLink to LLM SEO
LLM SEO is optimising your site and reputation so large language models, the AI models behind tools like ChatGPT and Gemini, name your brand when they answer.
Full guide: LLM SEO explained.
- llms.txtLink to llms.txt
llms.txt is a proposed markdown file at yoursite.com/llms.txt that points AI tools to your most useful pages.
Google says Google Search ignores it (does llms.txt work).
Terms starting with M
- Marketplace citationsLink to Marketplace citations
Marketplace citations are links to marketplace pages, such as pages on Amazon or Flipkart, that AI answers show as sources.
In the October 2026 re-run of our India study, amazon.in was cited in 132 of 479 AI shopping answers, more than any other site (English vs Hinglish study). Depra AI shows which marketplaces AI answers cite in your category and how often (marketplace intelligence). It does not track rankings inside a marketplace's own search.
Terms starting with O
- OAI-SearchBotLink to OAI-SearchBot
OAI-SearchBot is OpenAI's crawler for ChatGPT search, used to surface websites in ChatGPT's search results.
OpenAI says sites that opt out of it are not shown in ChatGPT search answers, though they can still appear as navigational links (OpenAI crawler docs (opens in a new tab)).
Terms starting with P
- Perplexity SonarLink to Perplexity Sonar
Perplexity Sonar is the answer model Perplexity sells through its API, which searches the live web and cites sources.
Depra AI uses Sonar for Perplexity answers and checks them daily, on every plan (Perplexity visibility tracker).
- PerplexityBotLink to PerplexityBot
PerplexityBot is Perplexity's crawler that surfaces and links websites in Perplexity search results.
Perplexity says it is not used to train AI foundation models (Perplexity crawler docs (opens in a new tab)).
- PromptLink to Prompt
A prompt is a question your buyers type into an AI tool, such as "best sunscreen for oily skin under ₹500".
A tracker asks it on a schedule to see which brands the answer names. Depra AI suggests 5 topics with 8 questions each.
Terms starting with Q
- Query fan-outLink to Query fan-out
Query fan-out is when an AI engine splits one question into several related searches and combines the results.
Google uses the term for AI Overviews and AI Mode (Google Search Central (opens in a new tab)). Depra AI stores the web searches ChatGPT ran behind an answer. The other engines do not report theirs. Full guide: what query fan-out is and which searches AI runs.
Terms starting with R
- RAG (retrieval-augmented generation)Link to RAG (retrieval-augmented generation)
RAG, short for retrieval-augmented generation, is a design where a system first fetches relevant documents and then has the language model write its answer from them.
AI search features that look up web pages before answering work this way.
- Rerun variationLink to Rerun variation
Rerun variation is the change in the brands named when the same question is asked again.
In our August 2026 test, two ChatGPT answers to the same question shared 54.7% of their brands on average, which is why one manual check is not enough (does ChatGPT give the same answer to everyone).
- RetrievalLink to Retrieval
Retrieval is the step where an AI engine searches the web or an index and pulls in pages before it writes.
Depra AI stores the pages an answer cites. It cannot see pages an engine read and chose not to cite.
- robots.txtLink to robots.txt
robots.txt is a text file at the root of your site that tells crawlers which pages they may fetch.
OpenAI and Perplexity say the fetchers they send when a user asks a question may not follow it (AI crawlers guide).
Terms starting with S
- Search crawlerLink to Search crawler
A search crawler is a bot that fetches pages so an AI engine can cite them in answers now, such as OAI-SearchBot or PerplexityBot.
Depra AI's AI crawler checker shows which of 41 AI crawlers your robots.txt allows.
- SentimentLink to Sentiment
Sentiment is whether an answer describes your brand positively, neutrally or negatively.
Depra AI keeps the quoted sentence so you can check each one.
Terms starting with T
- Training crawlerLink to Training crawler
A training crawler is a bot that collects pages to train AI models, such as GPTBot.
Blocking a training crawler is a separate choice from blocking the same vendor's search crawler.
Terms starting with V
- Visibility scoreLink to Visibility score
A visibility score is one percentage for AI visibility over a date range.
In Depra AI it is the answers that name you divided by all answers in the period (how Depra AI measures AI visibility).
Terms starting with Z
- Zero-click searchLink to Zero-click search
A zero-click search is a search where the person gets what they need on the results page, from a snippet or an AI Overview, and clicks no link.
What are AEO, GEO and AI SEO?
AEO, GEO, LLM SEO and AI SEO are overlapping names for the same work: getting your brand named and cited in AI answers.
Which AI engines and surfaces show AI answers?
Google AI Overviews, Google AI Mode, ChatGPT search, Perplexity and Gemini all show AI-written answers to a question.
How do AI engines build an answer?
AI search features look up web pages first and then write the answer from those pages.
What is a prompt, and why does its language matter?
A prompt is a question your buyers type into an AI tool, and the language it is typed in can change the answer.
How is AI visibility measured?
AI visibility is measured by how often answers name you, your share of brand mentions, your average position and the tone of each mention.
Which terms describe the sources and content behind AI answers?
Citations are the web pages an AI answer links to as its sources. The terms below cover those sources and the content formats AI cites.
What are AI crawlers, robots.txt and llms.txt?
AI crawlers are bots that fetch your pages, either to train AI models or so an engine can cite them in answers. robots.txt tells crawlers which pages they may fetch, and llms.txt is a proposed file that points AI tools to your most useful pages.
FAQ
What is the difference between a brand mention and a citation?
A mention is your brand's name in the text of an AI answer. A citation is a link to a web page that the answer shows as a source. An answer can name you without linking your site, and it can cite your site without naming you, so Depra AI records the two separately.
What is the difference between a training crawler and a search crawler?
A training crawler collects pages to build AI models. A search crawler fetches pages so an engine can cite them in answers today. OpenAI runs GPTBot for training and OAI-SearchBot for ChatGPT search, and you can allow or block each one separately in robots.txt (OpenAI crawler docs (opens in a new tab)).
Which of these terms does Depra AI measure?
Depra AI measures AI visibility, share of voice, average position, sentiment, cited sources, citation gaps, answer language and AI crawler access, for ChatGPT, Gemini, Perplexity, Google AI Overviews and every other AI engine you track, in English, Hinglish, French and most other major languages, plus code-mixed questions, on every plan. It also stores the web searches ChatGPT ran behind an answer, the one engine that reports them. Google AI Mode is available on Enterprise as an add-on. Depra AI does not capture counts of full questions or entity data. Where available, prompt volume shows measured DataForSEO keyword demand as a proxy for a prompt. The full method is in how Depra AI measures AI visibility.
