SEO & AEO Glossary

Plain-language definitions for every term that comes up building topical authority and optimizing for AI answer engines — no jargon left unexplained.

A B C D E F G H I K L M N O P R S T V Y Z

A

AEO (Answer Engine Optimization): The practice of structuring content so AI engines — ChatGPT, Perplexity, Google's AI Overviews, Claude — can reliably retrieve and cite it. AEO optimizes the chunk (a self-contained section) rather than the whole page, since that's the unit AI retrieval systems actually work with.; Chunking GEO (Generative Engine Optimization)RAG (Retrieval-Augmented Generation)
AI Overviews: Google's AI-generated summary shown above traditional search results for many queries, synthesized from multiple sources. Appearing in an AI Overview's citations is a distinct visibility surface from ranking in the traditional blue-link results below it.; AEO (Answer Engine Optimization)Zero-Click Search
Anchor Text: The visible, clickable text of a hyperlink. Search engines use anchor text as a signal for what the linked page is about — varied, natural anchor text pointing to the same page is a stronger signal than identical anchor text repeated site-wide, which can read as manipulative.

B

Backlink: A link from another website pointing to yours. Backlinks from relevant, credible sites remain one of the strongest ranking signals in traditional search, functioning as a vote of confidence from the linking site.; Domain Rating (DR)

C

Canonical Tag: An HTML tag (<link rel="canonical">) that tells search engines which version of a page is the "master" copy when duplicate or near-duplicate content exists at multiple URLs, consolidating ranking signals onto the canonical version.
Chunking: The process an AI retrieval system uses to split a page into smaller, independently-embeddable sections before searching them for relevance to a query. AEO writing practices — answer-first paragraphs, self-contained sections — exist specifically because content gets read this way, not as one continuous document.; AEO (Answer Engine Optimization)Vector Embedding RAG (Retrieval-Augmented Generation)
Content Cluster: A group of related pages (usually 5–15) that all link up to one central pillar page and down to each other, covering one subject in depth. Clusters are the structural unit topical authority is built from.; Pillar Page Topical Authority
Content Decay: The gradual loss of search rankings and traffic a page experiences over time as its information goes stale, competitors publish more current content, or search intent for its target query shifts. Countered by scheduled content refreshes, not one-time publishing.
Content Gap Analysis: The process of identifying questions or subtopics within a subject that your site hasn't covered yet but competitors — or the real query space — indicate matter. The output of a content gap analysis is usually new nodes to add to a topical map.; Topical Map
Content Pruning: Removing, merging, or substantially rewriting low-performing, outdated, or redundant pages. Done well, pruning can improve a site's overall quality signal by removing content that was dragging down the average.
Crawl Budget: The number of pages a search engine's crawler will visit on your site within a given time period. Mainly a concern for very large sites — thin, low-value pages can waste crawl budget that would otherwise go toward discovering and re-indexing important content.

D

Domain Authority (DA): A third-party (Moz) metric, scored 1–100, estimating how likely a domain is to rank in search results, based primarily on backlink profile. Not a metric Google itself uses or publishes — useful as a rough, third-party comparative signal, not a ranking factor.; Domain Rating (DR)Backlink
Domain Rating (DR): Ahrefs' equivalent third-party metric to Domain Authority, also scored 0–100 and based on backlink profile strength. Like DA, it's a comparative estimate from a specific tool, not a Google ranking factor.; Domain Authority (DA)

E

E-E-A-T: Experience, Expertise, Authoritativeness, Trustworthiness — the framework in Google's Search Quality Rater Guidelines for assessing content quality, weighted most heavily in YMYL categories like health, finance, and legal content.; YMYL (Your Money or Your Life)
Entity SEO: Optimizing content around real-world entities (people, places, organizations, concepts) that search engines recognize and connect via a knowledge graph, rather than optimizing purely for keyword strings. A central entity is the anchor a topical map is built around.; Knowledge Graph Topical Map

F

Featured Snippet: A highlighted answer box shown above regular results for certain queries, pulled directly from a ranking page's content. Concise, well-structured, question-answering content is more likely to be selected for this placement.

G

GEO (Generative Engine Optimization): A term some use interchangeably with AEO — optimizing content to be retrieved and cited by generative AI systems. AEO is the more commonly used term for this practice as it applies to AI-generated answers specifically.; AEO (Answer Engine Optimization)

H

Hreflang: An HTML attribute that tells search engines which language and regional version of a page to serve to users in different locales, preventing duplicate-content issues across international versions of the same content.

I

Index Bloat: A site having far more pages indexed by search engines than genuinely useful — often from thin, auto-generated, or duplicate pages. Index bloat can dilute a site's overall quality signal and waste crawl budget.; Crawl Budget Content Pruning
Indexing: The process by which a search engine adds a crawled page to its searchable database. A page can be crawled but not indexed if the engine judges it low-quality, duplicate, or otherwise not worth including.
Internal Linking: Hyperlinks between pages on the same site. Internal links distribute ranking signal, help search engines understand the relationship between pages, and ensure no page is an orphan reachable only through search.; Orphan Page Pillar Page

K

Keyword Cannibalization: When two or more pages on the same site compete for the same search query, splitting ranking signal between them instead of consolidating it onto one strong page. Usually fixed by merging the pages or clearly differentiating their intent.
Keyword Clustering: Grouping related keywords that share search intent into a single target page, rather than writing a separate page for every keyword variant. The practical test: if the top results for two queries substantially overlap, one page should serve both.; Content Cluster Search Intent
Knowledge Graph: A database of entities and the relationships between them, used by search engines to understand real-world concepts rather than just matching text strings. Entity SEO works by aligning content with how a subject sits in this graph.; Entity SEO

L

LLM (Large Language Model): A machine learning model trained on large amounts of text, capable of generating and understanding natural language. The AI engines relevant to AEO (ChatGPT, Claude, Perplexity, and others) are built on LLMs, often combined with retrieval systems.; RAG (Retrieval-Augmented Generation)
llms.txt: A plain-markdown file published at a site's root that gives AI engines a curated, human-written map of a site's most important content. An emerging convention, not a ratified standard, and not universally honoured yet — see the full guide for what to include.; Robots.txt Sitemap
Long-Tail Keyword: A longer, more specific search phrase with lower individual search volume but typically higher conversion intent and less competition than a short, generic "head" term.

M

Meta Description: The HTML tag providing a short summary of a page's content, often (though not always) shown as the snippet text under a result in search listings. Doesn't directly affect rankings but can influence click-through rate.

N

NLP (Natural Language Processing): The field of computing concerned with understanding and generating human language. Modern search engines use NLP to interpret query intent beyond exact keyword matching, and it underlies how LLMs process text.

O

Orphan Page: A page with no internal links pointing to it from anywhere else on the site, reachable only via direct URL, search, or the sitemap. Orphan pages are effectively invisible to both users navigating the site and, often, to search engines discovering new content.; Internal Linking

P

Pillar Page: The central, comprehensive page for one subject within a topical map, linking down to every cluster page beneath it and receiving links back up from each. The anchor of a content cluster.; Content Cluster Topical Map
Programmatic SEO (pSEO): Generating a large set of pages from a shared template and a structured dataset — e.g. one page per city, product, or comparison pair — to capture long-tail search volume at scale. Effective when each page has genuine, differentiated value; a well-documented risk when the template is thin and pages are interchangeable.

R

RAG (Retrieval-Augmented Generation): An AI architecture where a system retrieves relevant chunks of content from a knowledge source before generating an answer, rather than relying purely on what the model memorized during training. Most AI-search citation behavior works via some form of RAG.; Chunking Vector Embedding LLM (Large Language Model)
Robots.txt: A plain-text file at a site's root that tells crawlers which parts of the site they're allowed or disallowed to access. Controls access, unlike llms.txt, which curates content for engines that are already allowed in.; llms.txt

S

Schema Markup / Structured Data: Code (most commonly JSON-LD) added to a page that explicitly labels its content for machines — marking a section as a question-and-answer, a term-and-definition, an article with a named author, and so on. Reduces ambiguity for both classic search rich results and AI retrieval.
Search Intent: The underlying goal behind a search query — informational, navigational, transactional, or commercial-investigation. Content that matches the actual intent behind a query outperforms content that only matches the keyword string.; Keyword Clustering
Semantic Search: Search that matches based on meaning and context rather than exact keyword strings, using techniques like vector embeddings to understand that differently-worded queries can share the same underlying intent.; Vector Embedding
SERP (Search Engine Results Page): The page a search engine returns in response to a query, including organic results, ads, and features like featured snippets or AI Overviews.
Sitemap: An XML file listing a site's URLs, submitted to help search engines discover and crawl content efficiently. A complete, automated inventory — unlike llms.txt, which is a curated, hand-picked subset aimed at AI engines.; llms.txt

T

Topical Authority: A search engine's assessment that a site comprehensively covers a subject, built through complete coverage of a subject's real question space, structured and interlinked, rather than a handful of strong individual pages.; Topical Map Content Cluster
Topical Map: A planned inventory of every page a subject needs — pillar and clusters — mapped before writing begins, built by fanning out a central entity across intents (what, why, how, vs, for-segment) and clustering by shared search intent.; Topical Authority Pillar Page

V

Vector Embedding: A numerical representation of a piece of text that captures its meaning, allowing a computer to compare how semantically similar two pieces of text are. The mechanism AI retrieval systems use to find relevant chunks for a given query.; Chunking Semantic Search

Y

YMYL (Your Money or Your Life): Google's classification for content that could significantly impact a reader's health, financial stability, safety, or wellbeing if inaccurate — health, legal, and financial content are the clearest examples. YMYL content is held to a stricter quality and trust bar under Google's Search Quality Rater Guidelines.; E-E-A-T

Z

Zero-Click Search: A search where the user gets their answer directly on the results page (via a featured snippet, AI Overview, or knowledge panel) without clicking through to any website. A growing share of searches, and part of why citation in AI answers matters even without a click.; AI Overviews Featured Snippet

See these terms applied, not just defined.

The full method — mapping, structure, interlinking, AEO — is written out in the guides.