Reference · 54 terms

The AI Search Glossary

Working definitions for the metrics, platforms, surfaces, crawlers, and tactics shaping discovery across ChatGPT, Claude, Gemini, Perplexity, Copilot, Grok, Meta AI, Google AI Overviews, and AI Mode in 2026.

54 terms

Agentic browser Consumer Behaviour Also: AI browser: A browser (or browsing layer) that uses an LLM agent to interpret pages, summarise content, and take actions on behalf of the user. Arc Search, Perplexity Comet, Browser Company's Dia, Dia browser, and similar.
Ahrefs Brand Radar Tooling: Ahrefs' AI-visibility module tracking brand mentions and impressions inside AI answers. Surfaces shifts in how brands appear across ChatGPT, Gemini, and other LLM surfaces.
AI Mode Google Surface: Google's standalone AI-first search experience inside Search itself, a conversational, multi-step interface for complex queries. Different ranking and citation logic from classical SERP.
AI Overviews Google Surface Also: AIO, SGE: Google's generative answer shown at the top of the SERP for eligible queries. Sourced from the open web, cites multiple pages, and increasingly replaces the traditional snippet for informational intent. Successor to the SGE experiment.
AI-referred traffic AI Search Metric Also: AI traffic, LLM traffic: Sessions referred from ChatGPT, Claude, Gemini, Perplexity, Copilot, and other LLM surfaces. Often under-counted in standard analytics because referrers are stripped or labelled as direct.
Answer attribution rate AI Search Metric: The proportion of AI answers that explicitly link back to source pages versus those that summarise without attribution. Attribution rate varies materially by platform and query type.
Answer Engine Optimisation Search Tactic Also: AEO: The practice of structuring content so it can be lifted directly into AI answers. Close cousin of GEO; emphasises clean, parseable facts and unambiguous attribution.
Bounce-back rate (AI surface) AI Search Metric: The rate at which users return to the SERP or refine the prompt after seeing an AI Overview. Google's internal signal that an Overview failed, high bounce-back is associated with Overviews being silently removed for that query cluster.
Brand demand Consumer Behaviour: Search volume for branded terms. In an AI-search world, brand demand is the single strongest moat, generic queries are absorbed by AI Overviews and ChatGPT, while branded queries route users directly to brand properties.
Brand mention rate AI Search Metric: The frequency at which an LLM mentions a brand by name in answers across a prompt set, with or without citation. Brand mentions without citation are an early indicator of model-internalised brand awareness.
ChatGPT LLM Platform Also: GPT-4o, GPT-5, GPT-5.5, OpenAI ChatGPT: OpenAI's consumer assistant, the largest LLM surface by user count. Citation patterns shift materially with major model releases (e.g. GPT-5.5 in May 2026), and persistent memory now carries brand affinity across sessions.
Citation depth AI Search Metric Also: citation position: How early in an AI-generated answer a source is cited. Earlier citations correlate with higher click-through from AI surfaces and stronger user trust signals.
Citation diversity index AI Search Metric: The number of distinct domains an LLM cites across a prompt set, normalised by prompt count. Falling diversity in a category signals consolidation, and a closing window for new entrants.
Citation share AI Search Metric Also: SOV in AI, answer share, share of citations: The proportion of times a domain or page is cited inside AI-generated answers (ChatGPT, Claude, Gemini, Perplexity, AI Overviews) across a tracked prompt set. The AI-era equivalent of share-of-voice and the metric most predictive of branded discovery in 2026.
Citation-worthy content Search Tactic: Content with the qualities LLMs select for when synthesising an answer: a single, defensible claim per paragraph; named entities; first-hand evidence; and a clear authority signal.
Claude LLM Platform Also: Anthropic Claude, Claude Opus, Claude Sonnet: Anthropic's assistant. Strong on long-context analysis, tool use, and structured citation. Increasingly cited inside enterprise workflows where source attribution and reasoning quality matter.
ClaudeBot AI Crawler: Anthropic's web crawler. Powers Claude's retrieval and training. Honour robots.txt; access controls are increasingly material to citation share.
Consumer behaviour signal Consumer Behaviour: Observable patterns in how users phrase queries, refine searches, and choose answers, used by both ranking systems and generative models to infer intent and quality.
Copilot LLM Platform Also: Microsoft Copilot, Bing Chat: Microsoft's assistant, integrated across Bing, Windows, Office, and Edge. Pulls from the open web with Bing's index; visibility in Copilot is correlated with Bing ranking signals more tightly than other LLMs.
Core update Algorithm: A broad Google algorithm update affecting search rankings sitewide rather than a single feature. Recent core updates (e.g. May 2026) have increasingly favoured intent-aligned content over keyword-optimised content.
Digital discovery Search Tactic: The full set of channels through which people find brands, products, and answers, search engines, AI assistants, social platforms, marketplaces, and agentic browsers. Replaces the narrower frame of just “SEO”.
Discover Google Surface Also: Google Discover: Google's personalised feed in the Google app and on Android. Algorithmically curated, no query needed, driven by topical interest signals and freshness. Material traffic source for publishers.
EEAT Algorithm Also: E-E-A-T, Experience Expertise Authoritativeness Trustworthiness: Google's quality framework: Experience, Expertise, Authoritativeness, Trustworthiness. EEAT signals are increasingly weighted in both classical ranking and AI Overview source selection.
Gemini LLM Platform Also: Google Gemini, Gemini Advanced, Bard: Google's flagship assistant, integrated across Workspace, Android, and Search (AI Overviews and AI Mode use Gemini-family models). Brands optimising for Gemini reach are simultaneously optimising for AI Overviews.
Generative Engine Optimisation Search Tactic Also: GEO: The discipline of optimising content to be cited inside generative answers across ChatGPT, Claude, Gemini, Perplexity, and AI Overviews. Overlapping but distinct from classical SEO, favours specificity, citation-worthy claims, and structured attribution.
Google-Extended AI Crawler: Google's opt-out signal for using your content in Bard, Gemini, and AI-powered Search features without affecting classical Search ranking. A separate lever from Googlebot.
GPTBot AI Crawler: OpenAI's web crawler. Used to gather training data and to power ChatGPT browsing. Can be allowed or disallowed in robots.txt; blocking may reduce ChatGPT citation eligibility.
Grok LLM Platform Also: xAI Grok, Grok-2, Grok-3: xAI's assistant, surfaced primarily inside X (formerly Twitter) and via the standalone Grok app. Distinctive for real-time access to the X firehose, which makes it the fastest LLM surface for current-events and live-trend queries, a different discovery shape from retrieval-grounded competitors.
Helpful Content Update Algorithm Also: HCU: Google's quality-focused update class targeting low-value, AI-generated, or thin content. Successive HCUs have favoured first-hand experience and named expertise over comprehensive but shallow coverage.
Intent resolution Search Tactic: How completely a page answers the underlying job the searcher was trying to do, not whether it matches the keywords used. The dominant ranking factor post-Google May 2026 core update.
Job-to-be-done (search) Consumer Behaviour Also: JTBD: The functional outcome a searcher is trying to achieve when they issue a query. Distinct from the literal query text. The unit of analysis for intent-aligned content strategy.
JSON-LD Structured Data: The recommended syntax for embedding Schema.org structured data on a page. Lightweight, decoupled from page HTML, and increasingly the format LLMs prefer when retrieving structured facts.
Knowledge graph entity Structured Data: A node in Google's Knowledge Graph representing a real-world thing (person, place, organisation, work). Strong entity signals are prerequisite for Search Profile eligibility and consistent AI Overview attribution.
Knowledge Panel Google Surface: The right-rail entity summary on a Google SERP. Driven by the Knowledge Graph and structured data; foundational entity surface that increasingly feeds Search Profile and AI Overview content.
LLM crawler share AI Search Metric: The proportion of crawler traffic to your site coming from AI bots (GPTBot, ClaudeBot, Google-Extended, PerplexityBot) vs. classical crawlers (Googlebot, Bingbot). A leading indicator of upcoming citation activity.
LLM-friendly content Search Tactic: Content structured to be parseable and citation-worthy by language models: clear claims, specific facts, named sources, structured data, and unambiguous attribution.
Meta AI LLM Platform Also: Llama, Meta Llama: Meta's assistant, powered by Llama models and surfaced inside WhatsApp, Instagram, Messenger, and Facebook. Discovery channel reach grows with each new Llama release.
OAI-SearchBot AI Crawler: OpenAI's user-agent for ChatGPT Search retrieval (distinct from GPTBot, which is for training). Allowing this is required for inclusion in ChatGPT Search results.
Perplexity LLM Platform Also: Perplexity AI, Perplexity Comet: An answer engine that combines retrieval with LLM synthesis and shows inline citations by default. Higher attribution rate than most platforms, citations are part of the product, not an afterthought.
PerplexityBot AI Crawler: Perplexity's crawler. Allows real-time retrieval for Perplexity answers. Blocking reduces eligibility for Perplexity citation.
Profound Tooling: AI-visibility platform for marketers tracking brand mentions and citation share across LLM surfaces. Added Documents (June 2026) and a redesigned Sentiment tool to move beyond surface-level metrics.
Project Glasswing Tooling: Anthropic's research initiative supporting organisations applying AI to high-stakes problems. Expanded in June 2026 to approximately 150 new organisations across 15 countries.
Prompt visibility AI Search Metric Also: prompt coverage: The percentage of monitored prompts in which a brand or domain appears at least once in the generated answer. The AI-search analogue of keyword ranking coverage.
Prompt-shaping behaviour Consumer Behaviour: How users refine the language of their prompts mid-conversation to get a better answer. Reveals a shift from keyword behaviour (typing fewer terms) to conversation behaviour (typing more, more naturally).
Retrieval-augmented generation Structured Data Also: RAG: A generation approach where an LLM pulls relevant documents at query time and uses them as the source for its answer. The pattern behind most enterprise AI search products and Perplexity-style answer engines.
Schema.org Structured Data: The shared vocabulary for structured-data markup used by Google, Microsoft, and major search engines. As of June 2026, Schema.org publishes monthly aggregate adoption statistics by type.
Search Profile Google Surface Also: Google Search Profile: A dedicated profile surface for publishers, creators, and brands inside Google Search (launched June 2026). Lets verified entities control bio, recent work, and links shown for branded and named-entity queries.
SERP volatility Algorithm: The rate of change in search result rankings over a time window. High volatility usually signals a core update or major spam action in progress.
SISTRIX Tooling: SEO visibility platform widely used for post-core-update analysis. Source of the analysis that showed Google's May 2026 update favoured intent-aligned pages and the GPT-5.5 citation-pattern shift.
Source recency AI Search Metric: How recent the sources cited in an AI answer are. Recency-weighted models favour fresh content; signals when an LLM is treating a topic as time-sensitive.
Structured data Structured Data: Markup (typically JSON-LD using Schema.org vocabulary) that tells search engines and LLMs what the entities and relationships on a page are. Increasingly important as both Google and generative systems converge on entity-level understanding.
Synthetic prompt panel AI Search Metric Also: prompt set, evaluation set: A curated set of representative prompts run against multiple LLMs on a schedule to track citation share, brand mentions, and visibility over time. The AI-search equivalent of a rank-tracker.
Topical authority Algorithm: The perceived depth and breadth of a domain's coverage of a topic. Post-HCU, depth + first-hand expertise are weighted more heavily than breadth.
Zero-click query AI Search Metric Also: zero-click search: A query the user resolves on the SERP itself without clicking any result. Zero-click rates have risen sharply with the rollout of AI Overviews and persistent ChatGPT memory.

The AI Search Glossary

Stay ahead of AI Search