Glossary

AEO stands for answer engine optimization: the practice of structuring content so an answer engine can extract it as a direct answer. In marketing contexts AEO almost always means this. The same three letters are used for account executive operations and for aerospace engineering, which are unrelated.

AI Overviews are AI-generated summaries Google places above the traditional results for many queries. They synthesize several sources into a short answer with links to what was used, pushing the classic blue links further down the page and often resolving the query without a click.

AI search is any search experience that returns a written, synthesized answer rather than a ranked list of links. It covers dedicated assistants like ChatGPT and Perplexity, and AI layers built into traditional engines such as Google's AI Overviews and AI Mode.

AI SEO is used for two different practices. The first is optimizing so your brand appears in AI-generated answers — the same work as generative engine optimization. The second is using AI tools to produce SEO work faster. They share a name and almost nothing else.

An answer engine is a system that responds to a question with a synthesized answer rather than a ranked list of links. ChatGPT, Perplexity, Gemini, Claude and Google's AI Overviews are answer engines. They read a small set of sources, write a single response, and cite some of what they read.

Answer engine optimization (AEO) is the practice of structuring content so that an answer engine can extract it as a direct answer to a question. It targets the passage rather than the page: a question-shaped heading with a complete, self-contained answer directly beneath it.

ChatGPT SEO is the practice of getting a brand named and cited in ChatGPT's answers. Because ChatGPT searches the live web before answering most commercial questions, the practical target is the pages it retrieves and the third-party sources that name you — not the model's training data.

Conversational search is querying a search system in natural language — full questions rather than keyword fragments — often across several turns where each question builds on the last. It is the input style answer engines are designed for, and it makes the question, not the keyword, the unit of demand.

Generative engine optimization (GEO) is the practice of getting a brand named and cited inside answers produced by AI engines such as ChatGPT, Gemini, Perplexity and Google's AI Overviews. Where SEO competes for a position in a ranked list of links, GEO competes for a place inside a single synthesized answer.

AI Mode is Google's conversational search experience: a dedicated interface where the response is a written answer you can follow up on, rather than an AI summary sitting above a results page. It replaces the ten-link page entirely for the queries it handles.

LLM SEO is the practice of influencing what large language models say about your brand — getting named in their answers and cited in their sources. It is a synonym for generative engine optimization, emphasising the model rather than the product built on top of it.

Search everywhere optimization is the practice of optimizing for every platform where people search, rather than for web search alone. It treats YouTube, TikTok, Reddit, Amazon, app stores and AI assistants as distinct search channels, each with its own ranking behaviour and its own audience.

An AI citation is a source that an answer engine links or attributes when producing an answer. Being cited means the engine used or referenced your page. It does not mean the answer recommended your brand — those are separate outcomes, and roughly six in ten citations never name the brand they cite.

AI share of voice is the portion of all brand mentions across AI answers to your tracked questions that belong to you. If ten answers name brands twenty times and four of those are you, your share is twenty percent. It is read alongside average position, per engine, across runs.

AI visibility is how often AI answer engines name and cite your brand in response to the questions your customers ask. It is measured as two separate rates per engine — how often the prose names you, and how often the citations include your domain — tracked across repeated runs rather than single answers.

A brand mention is when the prose of an AI answer names your brand. It is tracked separately from a citation, which only means the answer's source list included your domain. A mention puts your name in front of the reader; a citation may not.

Brand monitoring is the systematic tracking of where and how a brand is mentioned across the web — press, social platforms, forums, reviews and increasingly AI answers. Its purpose is to turn scattered mentions into something countable, so changes in perception and visibility are noticed rather than guessed at.

Brand sentiment is the emotional tone of what is said about a brand — positive, negative or neutral — measured across mentions and aggregated into a trend. In AI answers it extends beyond tone to accuracy: how an engine characterises your product matters as much as whether it sounds favourable.

Brand visibility is how often and how prominently a brand appears in the places its buyers are looking. It has traditionally been measured through search rankings, impressions and media coverage; the newer and harder component is whether AI answer engines name the brand when asked what to buy.

Citation rate is the proportion of AI answers to your tracked questions whose sources include your domain. It is tracked separately from mention rate — how often the prose names you — because a brand can be cited constantly without ever being recommended.

Competitive benchmarking is measuring your performance against named competitors using the same metric, the same method and the same time window. In AI visibility it means running one fixed question set and recording which brands each engine names, so relative position is comparable rather than anecdotal.

A ghost citation is an AI answer that cites your page as a source without ever naming your brand in the prose. The engine used your content and attributed it in a link list, but the reader sees a recommendation for somebody else. Around six in ten AI citations are ghost citations.

Share of search is a brand's proportion of all branded search volume within its category — how many people search for you versus your competitors. It is used as a fast, cheap proxy for market share, and it tracks demand rather than the visibility that creates it.

An AI hallucination is a statement produced by a language model that is fluent, confident and false. It happens because models predict likely text rather than retrieve verified facts, so a plausible-sounding answer is generated with the same confidence as a correct one.

Content freshness is how current a page's information is, and the weight search and AI systems give to that. Pages kept genuinely current earn meaningfully more AI citations than pages left to sit, which makes freshness the best-evidenced on-site visibility lever you fully control.

Entity SEO is the practice of making search and AI systems recognise your brand as a distinct, well-defined thing rather than a string of characters. It covers consistent naming, unambiguous descriptions, and corroboration across independent sources so a system can confidently identify who you are.

A fan-out query is one of the internal searches an AI engine runs to research a user's question before answering it. One customer question typically fans out into several narrower queries, and the pages that satisfy those queries are the ones that end up cited.

Grounding is the practice of connecting a language model's answer to specific external sources retrieved at answer time, rather than relying on what the model memorised during training. A grounded answer can cite where each claim came from, which is what makes citations — and therefore AI visibility — possible at all.

A large language model is a neural network trained on very large amounts of text to predict likely continuations of language. That single capability produces answering, summarising and writing. It is the component underneath ChatGPT, Claude, Gemini and the AI features inside search engines.

Passage retrieval is the practice of splitting documents into sections and retrieving and ranking those sections independently, rather than treating a page as one unit. It is why a long page can be pulled into an answer on the strength of one paragraph, and ignored despite being strong overall.

Retrieval-augmented generation is a technique where a system retrieves relevant documents and places them in a language model's context, so the model answers from those sources rather than from memory alone. It is how AI answers come to have citations, and how live information reaches a frozen model.

Semantic search matches queries to content by meaning rather than by matching words. Text is converted into vectors — numerical representations where similar meanings sit close together — so a query can retrieve a passage that answers it without sharing any of its vocabulary.

Topical authority is the degree to which a site covers a subject comprehensively and credibly, rather than touching it once. It is built by covering a topic's real question space in depth, with internal connections between the pieces, and it makes a site a more reliable source to retrieve from.

Brand authority is the credibility a brand has earned in its category, and the signals that communicate that credibility to people and to search systems. It is built through independent corroboration — what others say about you — far more than through anything you publish about yourself.

A knowledge graph is a structured database of entities — people, companies, products, places — and the relationships between them. Search and AI systems use one to understand that a query is about a specific thing, and to retrieve facts about it rather than pages mentioning it.

Wikidata is a free, collaboratively edited knowledge base of structured facts about entities, each identified by a unique QID. It is machine-readable by design and widely consumed by search engines and AI systems, which makes an accurate entry a useful anchor for entity recognition.

An AI crawler is an automated bot that fetches web pages on behalf of an AI company, either to build a training corpus, to maintain a search index, or to retrieve a page live while answering a user's question. Each is identified by a named user agent you can allow or block in robots.txt.

CCBot is the crawler operated by Common Crawl, a non-profit that publishes a free, openly available archive of the web. Because that archive is a common source of AI training data, CCBot is often included in robots.txt decisions about AI access even though Common Crawl is not an AI company.

ClaudeBot is Anthropic's web crawler, used to gather publicly available content for Claude. A separate agent, Claude-User, fetches a specific page live when a user's request requires it. Both are identified by name in robots.txt and can be allowed or disallowed independently.

Google-Extended is a robots.txt token that controls whether Google may use your content to ground and improve its generative AI products, including Gemini and AI Overviews. It is not a crawler — Googlebot still fetches your pages for search regardless of what you set.

GPTBot is OpenAI's crawler for gathering publicly available web content used in training its models. It is one of three OpenAI agents: GPTBot for training, OAI-SearchBot for the search index behind ChatGPT's answers, and ChatGPT-User for fetching a page live when a user's question requires it.

llms.txt is a proposed convention — a markdown file at your site root that summarizes your content for large language models. No major AI engine has been shown to read it, and publishing one has no measured effect on whether you get cited.

PerplexityBot is Perplexity's crawler, used to index pages for the search product behind its answers. Perplexity-User is the separate agent that fetches a page live when a user's question requires it. Both can be allowed or blocked by name in robots.txt.

robots.txt is a plain-text file at your site root that tells automated crawlers which paths they may fetch. Each block names a user agent and lists allow and disallow rules. It is advisory rather than enforced, and it controls crawling rather than indexing or access.

Structured data is machine-readable markup — usually schema.org vocabulary in JSON-LD — that states explicitly what a page is about: an article, a product, a definition, an FAQ. Search engines use it for rich results and entity understanding rather than as a ranking factor.

A content refresh is the substantive update of an existing page — correcting facts, adding current data, and revising what changed — rather than publishing something new. Pages that are kept current earn meaningfully more AI citations than pages left to sit, making it the best-evidenced on-site visibility lever you fully control.

Digital PR is the practice of earning coverage, mentions and links on publications you do not own, using newsworthy material rather than paid placement. Because AI answer engines name brands they encounter on the sources they read, earned coverage now influences AI recommendations as directly as it influences reputation.

A directory listing is a business's entry on a third-party directory or review platform — a Google Business Profile, Yelp, G2, an industry directory. Listings matter for AI visibility because engines read them as corroborating sources when deciding which brands to name, particularly for local and category questions.

Guest posting is writing an article published on another organisation's site, usually in exchange for a byline and a link. Done for genuine audience reach it remains legitimate; done at scale purely for links it is a well-documented pattern search engines discount and sometimes penalise.

A listicle is an article structured as a numbered or bulleted list — most commercially, the 'best X for Y' roundup. Third-party listicles are disproportionately cited by AI answer engines, which makes being included in one of the strongest external levers available for getting named in answers.

Parasite SEO is publishing content on a high-authority third-party site in order to rank on that site's reputation instead of your own. Google named the tactic site reputation abuse in March 2024 and has issued manual actions against host sites since May 2024, which largely ended its commercial form.

User-generated content is material created by users rather than by a brand or publisher: reviews, forum threads, comments, community posts and social content. It is disproportionately cited by AI answer engines, which makes the platforms hosting it a significant visibility channel.

A featured snippet is a passage Google extracts from a ranking page and displays at the top of results to answer a query directly, with attribution and a link. Unlike an AI Overview it quotes one source verbatim rather than synthesizing several.

A SERP is a search engine results page — everything returned for a query, not just the ten blue links. It includes ads, featured snippets, local packs, image and video blocks, People Also Ask, and increasingly an AI-generated answer above all of them.

A zero-click search is one where the user gets what they needed without clicking through to any website — the answer appeared in the results page or in an AI-generated response. The share has risen sharply as answer engines and AI Overviews satisfy more questions directly.