The AI search vocabulary, defined plainly.

AEO (Answer Engine Optimization)

Answer engine optimization is the practice of making a business the answer AI assistants give, rather than one result among ten blue links. It covers the work that makes a business easy for an assistant to identify and quote: entity clarity, structured data, third-party corroboration, and content direct enough to lift verbatim.

Go deeper: AEO vs SEO

GEO (Generative Engine Optimization)

Generative engine optimization is a near-synonym of AEO used when the emphasis is on generative systems like ChatGPT, Gemini, and Perplexity composing original answers. The work is the same: make a business easy for a model to find, verify, and confidently include in a generated recommendation.

AI visibility score

An AI visibility score is a 0 to 100 measure of how often AI assistants name a business when buyers ask who to hire. Sightline's paid audit runs a fixed panel of buyer prompts, records who is named and how prominently, and reports site and reputation signals beside that number, not inside it. The free check's score blends them in.

Go deeper: How to read yours

Mention rate

Mention rate is the share of answered checks in a tracked prompt panel that name a business, where one check is one buyer prompt put to one AI engine. In Sightline's reports it counts for 40% of the AI visibility score. Some panel prompts name the business directly, so it is not a rate of unprompted recommendations.

Go deeper: Reading your monthly report

Share of voice

Share of voice is a business's portion of the mentions split between it and a chosen set of competitors across a tracked panel of AI answers. In Sightline's reports it is your mentions divided by your mentions plus every mention of the competitors listed for you: if you are named 8 times and your listed rivals 12 times in total, your share of voice is 40%. It differs from mention rate, the share of answers that name you at all.

Go deeper: How to use yours

Buyer prompt

A buyer prompt is the literal question a customer asks an AI assistant when they are ready to choose a provider, like who is the best HVAC company near me. Tracking a fixed panel of these prompts month over month is how AI visibility becomes measurable instead of anecdotal.

Answer engine

An answer engine is any system that responds to a question with a composed answer instead of a list of links: ChatGPT, Claude, Perplexity, Gemini, Google AI Overviews, and Copilot all qualify. Being one of the few names inside the answer is the new version of ranking.

Entity authority

Entity authority is how confidently an AI system can identify who a business is, where it operates, and what it does, based on agreement across its website, profiles, listings, and independent mentions. Assistants recommend businesses they are sure about; contradictions between sources quietly remove you from answers.

Go deeper: Entity authority basics

E-E-A-T

E-E-A-T stands for experience, expertise, authoritativeness, and trustworthiness: the qualities Google's search quality rater guidelines ask human raters to judge, and that Google says its systems try to identify in content. Google also says E-E-A-T is not a specific ranking factor, and that trust matters most. On a business site it shows up as named people, credentials, and first-hand work.

Structured data (JSON-LD)

Structured data is machine-readable markup, usually JSON-LD using schema.org vocabulary, that states a site's facts in a format engines parse directly: name, services, area served, prices, FAQs. It lets AI confirm facts instead of inferring them from prose, which makes every other signal more legible.

Citation

A citation is an independent mention of a business that AI systems can find and cite: a directory listing, a roundup, a news mention, a review platform profile. Citations corroborate what a business says about itself, and corroboration is what turns a claim into something an assistant will repeat.

Go deeper: How citation building works

NAP consistency

NAP consistency means a business's name, address, and phone number appear identically everywhere they are published. Inconsistent listings read to machines as possibly different businesses, which fragments the entity and weakens every downstream signal, from local rankings to AI recommendations.

Data aggregator

A data aggregator is a company that collects business records (name, address, phone, category) and supplies them in bulk to directories, map apps, and other platforms. Data Axle, Foursquare, and TransUnion (the former Neustar Localeze) are current examples. One wrong aggregator record can spread to many listings, which is why correcting bad records matters more than buying new submissions.

Go deeper: Which citations still matter

llms.txt

llms.txt is a plain-text file at a site's root that gives AI systems a curated orientation: what the business is, its key pages, and its facts, in prose a model can read in one pass. It complements robots.txt (permissions) and structured data (machine-readable facts).

Go deeper: llms.txt, explained

Google AI Overviews

AI Overviews are the generated summaries Google places above traditional results for many searches, composed from sources its systems consider reliable. For local services they often name specific providers, which makes the signals behind that selection part of the same visibility work as chat assistants.

Google AI Mode

AI Mode is Google's chat-style search mode: a searcher asks a question, can ask follow-ups, and gets a generated answer with links to its sources instead of a list of results. It is separate from AI Overviews, the summary shown above ordinary results, and the two can cite quite different sources for the same local question.

Go deeper: What local AI answers cite

Map pack

The map pack is the short list of local businesses, shown with a map, that Google places in its results when a search has local intent, such as plumber near me. The listings come from Google Business Profiles, and Google names relevance, distance, and prominence as the main factors behind its local results.

Go deeper: Google Business Profile guide