The SEO glossary for buyers
Short, sourced definitions of the terms that come up when you buy search work: SEO, GEO and AI search, conversion rate optimization, analytics and the platforms your site runs on. Each entry opens on a plain answer, says why it matters to you, and links to the deeper guide.
30 minutes. No pitch deck. You leave with a prioritised plan.
Search has picked up a second vocabulary in two years. The old one, rankings, backlinks, Core Web Vitals, never went away, and a new one arrived on top of it: AI Overviews, AI Mode, query fan-out, citations, GEO. Proposals mix the two freely, and it is hard to judge a plan when half of its nouns are unfamiliar.
This glossary is the reference we wish buyers had before a sales call. Every entry opens on a definition short enough to read in one breath, then says two things a generic dictionary does not: why the term should matter to someone paying for the work, and how it is actually measured or applied. Where a claim rests on a search engine's documentation or a piece of research, the source is listed at the foot of the entry.
How is the glossary organised?
Alphabetically, with a filter for five areas: SEO, GEO and AI search, conversion rate optimization, analytics, and the platforms sites are built on. Terms link to their neighbours, so an entry on AI Overviews points on to query fan-out and zero-click searches, and each one links down to the longer guide on the blog when that guide is live.
What will you not find here?
Invented numbers. Where a figure appears it comes from the named source. We also leave out jargon that exists only to sell a tool, and we say plainly when a term is overhyped, as the entry on llms.txt does.
A
- Alt text
- Alt text is a written description added to an image's HTML alt attribute.
- Anchor text
- Anchor text is the visible, clickable words in a hyperlink.
B
- Backlink
- A backlink is a link from another website to a page on your site.
- Breadcrumbs
- Breadcrumbs are a row of links near the top of a page showing the path back to the homepage through each parent category, such as Home, then Shoes, then Running Shoes.
C
- Canonical URL
- A canonical URL is the one version of a page that a site owner or a search engine treats as the master copy when several URLs show the same or very similar content.
- Content decay
- Content decay is the gradual loss of search traffic a page experiences over time as its information goes out of date, competitors publish more current pages, or the query it targets changes in intent, even though the page itself was never edited or removed.
- Core update
- A core update is a broad change Google makes to its main ranking systems, rolled out several times a year and announced publicly, that can move rankings across many sites and topics at once.
- Core Web Vitals (CWV)
- Core Web Vitals (CWV) are three Google metrics that describe real users' experience of a page: Largest Contentful Paint for loading, Interaction to Next Paint for responsiveness, and Cumulative Layout Shift for visual stability.
- Crawling
- Crawling is the process by which a search engine's automated bot, such as Googlebot, follows links and sitemap entries to discover URLs on the web and download their content.
- Cumulative Layout Shift (CLS)
- Cumulative Layout Shift is a Core Web Vitals metric that scores how much a page's visible content unexpectedly moves as it loads, such as text jumping down when an ad or image loads late.
D
- Disavow file
- A disavow file is a list of backlinks or linking domains a site owner submits to Google, asking Google to ignore them when assessing the site, typically because the links were bought, come from a spam attack, or are otherwise damaging and cannot be removed directly at the source.
- Domain Authority (DA)
- Domain Authority is a third-party metric from Moz, scored 0 to 100, that predicts how well a whole domain is likely to rank in search results based on its backlink profile.
- Duplicate content
- Duplicate content is substantial text that appears, identically or in near-identical form, on more than one URL, whether within one site or across different domains.
E
- E-E-A-T
- E-E-A-T stands for experience, expertise, authoritativeness and trustworthiness.
F
- Faceted navigation
- Faceted navigation is the filter and sort system on a catalogue page, such as filtering by size, colour or price, that lets a visitor narrow a list of products.
- Featured snippet
- A featured snippet is a short extract from a web page that Google shows above or near the top of the organic results, answering the query directly in a paragraph, list or table, with a link to the page it came from.
G
- Google Business Profile (GBP)
- A Google Business Profile (GBP) is the free listing a business manages in Google that appears in Maps and in the local results on Search.
H
- Helpful content system
- The helpful content system is a Google ranking system, now built into its core ranking, that is designed to reduce visibility for content made primarily to rank in search rather than to genuinely help the person reading it, and to reward content that shows real expertise and first-hand knowledge.
- Hreflang
- Hreflang is an HTML or sitemap annotation that tells search engines which language and, optionally, which country a page is written for, and points to the equivalent page in each other language or region a site offers, so the right version is shown to each searcher.
I
- Indexing
- Indexing is the process by which a search engine analyses a crawled page and stores it in its index, the database it actually searches when answering a query.
- IndexNow
- IndexNow is a protocol that lets a website instantly notify participating search engines, currently Bing and Yandex among others, when a page has been added, updated or deleted, instead of waiting for the engine to discover the change on its own next crawl.
- Interaction to Next Paint (INP)
- Interaction to Next Paint is a Core Web Vitals metric that measures how long a page takes to visibly respond after a visitor clicks, taps or types, sampled across every interaction during a visit.
- Internal link
- An internal link is a hyperlink from one page to another page on the same website.
J
- JavaScript rendering
- JavaScript rendering is the process of running a page's JavaScript to build the final HTML a visitor sees, rather than serving that HTML directly from the server.
- JSON-LD
- JSON-LD is the data format Google recommends for adding schema markup to a page: a self-contained block of JavaScript-like code, usually placed in the page head, that states structured facts about the page without needing to be woven into the visible HTML the way older microdata formats did.
K
- Keyword difficulty
- Keyword difficulty is a score, usually 0 to 100, that a keyword research tool assigns to estimate how hard it would be to rank on the first page for a given search term, typically based on the authority and number of backlinks held by the pages currently ranking for it.
L
- Largest Contentful Paint (LCP)
- Largest Contentful Paint is a Core Web Vitals metric that measures how long it takes for the biggest visible element, usually a hero image, headline or block of text, to render on screen after a visitor opens the page.
- Link equity
- Link equity is the value or authority passed from one page to another through a hyperlink, influenced by the relevance and authority of the linking page and site.
- Local pack
- The local pack is the block of usually three local business listings, shown with a map, that Google displays for searches with local intent, such as "plumber near me." It sits above ordinary organic results and is driven mainly by a Google Business Profile rather than the website itself.
- Long-tail keyword
- A long-tail keyword is a longer, more specific search phrase, such as "best waterproof running shoes for flat feet," that gets less search volume individually than a broad term like "running shoes" but is usually easier to rank for and converts better because it matches a clearer intent.
M
- Manual action
- A manual action is a human reviewer at Google's decision to reduce or remove a specific site's visibility because it violates Google's spam policies, such as unnatural links, thin content or cloaking.
- Meta description
- A meta description is an HTML tag that summarises a page's content in a sentence or two.
- Mobile-first indexing
- Mobile-first indexing means Google predominantly uses the mobile version of a page's content, crawled by its smartphone crawler, to index and rank that page, rather than the desktop version.
N
- NAP consistency
- NAP consistency is having the exact same business name, address and phone number listed identically across a website, its Google Business Profile, and every directory or citation source it appears on.
- Nofollow
- Nofollow is a link attribute, rel="nofollow", that tells search engines not to pass ranking credit through that link.
- Noindex
- Noindex is a directive, set through a meta robots tag or an X-Robots-Tag HTTP header, that tells a search engine not to include a specific page in its index at all.
O
- Off-page SEO
- Off-page SEO covers the work done outside a site's own pages to improve its search visibility, chiefly earning backlinks, but also digital PR, brand mentions, reviews, and citations.
- On-page SEO
- On-page SEO is everything a site controls directly on its own pages to help them rank: content quality, title tags, headings, internal links, structured data, page speed and mobile usability.
- Orphan page
- An orphan page is a page on a website that has no internal links pointing to it from anywhere else on the site, so a visitor or crawler cannot reach it by browsing normally, only by a direct URL, an external link, or a sitemap entry.
P
- People Also Ask (PAA)
- People Also Ask is a Google search results feature showing an expandable list of related questions, each revealing a short answer pulled from a specific web page when clicked.
- Pillar page
- A pillar page is a broad, comprehensive page covering a core topic at a high level, linked to and from a set of narrower supporting pages that each go deeper into one subtopic.
R
- Redirect (301 and 302)
- A redirect automatically sends a visitor and a search engine from one URL to another.
- Rich results
- Rich results are search results shown with extra visual detail beyond a plain blue link, such as star ratings, product prices, recipe images or event dates, generated when a page's structured data qualifies for one of Google's supported result types.
- robots.txt
- robots.txt is a plain text file at a site's root that tells crawlers which parts of the site they may or may not fetch, by user agent.
S
- Scaled content abuse
- Scaled content abuse is Google's spam policy term for publishing large volumes of pages, whether written by people, automated tools or AI, primarily to manipulate search rankings rather than to genuinely help the reader.
- Schema markup
- Schema markup is structured data added to a web page, usually as JSON-LD, that uses the Schema.org vocabulary to state facts about the page in a form machines can read without guessing: who published it, what product or service it describes, its price, its author and how it relates to other things.
- Search engine optimization (SEO)
- Search engine optimization (SEO) is the work of improving a website so that search engines can crawl, understand and rank its pages for the searches its buyers make.
- Search engine results page (SERP)
- A search engine results page (SERP) is the page a search engine shows in response to a query.
- Search volume
- Search volume is an estimate of how many times a given keyword is searched, usually reported as a monthly average, by a keyword research tool.
- SERP feature
- A SERP feature is any element on a search results page beyond the standard list of blue links, such as a featured snippet, People Also Ask box, local pack, image carousel or AI Overview.
- Sitemap
- A sitemap is an XML file listing the URLs on a site that a business wants search engines to know about, optionally with metadata like when each was last modified.
T
- Thin content
- Thin content is a page that adds little or no original value for a reader: very short, auto-generated, scraped from elsewhere, or a near-duplicate of other pages on the site with only small variables swapped.
- Title tag
- A title tag is the HTML element that names a page, shown as the clickable headline in search results and as the browser tab label.
Y
- YMYL (Your Money or Your Life)
- YMYL is Google's term for topics that could significantly affect a reader's health, financial stability, safety or major life decisions, such as medical, legal or financial content.
Questions we get asked
Who writes these definitions?
The two founders, Ibrahem Helal and Jeremy Zava, write and review every entry. Each one names at least one source you can check, usually the search engine's own documentation or the original research, so you are not taking a definition on our word alone.
Why does every entry open with a short paragraph?
Because that paragraph is the answer. It is written to make sense on its own in forty to sixty words, which is also the shape search features and AI assistants quote. The rest of the entry says why the term matters to a buyer and how it is measured or applied.
What is the difference between SEO, GEO and AEO?
SEO gets pages ranked in search results. GEO gets a brand named and cited in answers from assistants such as ChatGPT, Perplexity, Claude and Google's AI features. AEO is the older label for structuring answers so search features can lift them. The work overlaps heavily, and each has its own entry here.
How often are new terms added?
Two a day from 24 September 2026 until the planned list of 120 terms is complete, then as new terms enter common use. Entries are updated when the underlying documentation changes, and the date on each entry says when that last happened.
Can I quote or link to a definition?
Yes. Link to the entry's own page so readers get the source list with it. If a definition is wrong or out of date, email us and we will correct it and change the date on the entry.
Do you sell every service described here?
No. The glossary covers terms buyers meet whoever they hire. Where we do the work, the entry links to the service page; where we do not, it says what the term means and stops there.
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30 minutes. No pitch deck. You leave with a prioritised plan.