SEO comes with a lot of jargon. “Your canonical points to a noindexed URL, and the SERP shows a featured snippet for that long-tail query.” If a sentence like that makes your head spin, you are not alone. Beginners often tell me the words are harder than the work.
This glossary explains 74 of the most useful SEO terms in plain English, from A to Z. Each definition is short, and each one links to the lesson in this course that explains the idea properly, with examples.
After this lesson, you will be able to read an SEO report, a tool’s dashboard or an agency proposal and understand what it is saying. I suggest bookmarking this page and coming back whenever you meet a word you don’t know.
SEO terms from A to C
- AI Mode: Google’s conversational search experience, where you can ask longer questions and follow-ups and get an AI-written answer with links. See the lesson on AI Overviews and AI Mode.
- AI Overviews: AI-generated summaries that appear at the top of some Google results, with links to the pages they draw from. See how AI Overviews work.
- Algorithm update: A change Google makes to how it ranks results. Big, broad changes are called core updates; Google lists confirmed ones on its Search Status Dashboard. See the lesson on algorithm updates.
- Alt text: A short written description of an image, added in the image’s code. It helps people using screen readers and helps search engines understand the image. See image SEO basics.
- Anchor text: The clickable words of a link. Descriptive anchor text tells readers and search engines what the linked page is about. See the lesson on internal linking.
- Backlink: A link from another website to yours. Good backlinks act like recommendations and are one of the signals Google uses. See what backlinks are.
- Black hat SEO: Tactics that try to trick search engines and break Google’s spam policies, such as hidden text or bought links. They risk penalties. See white hat vs black hat SEO.
- Breadcrumbs: A small trail of links (Home > Shoes > Running) that shows where a page sits on your site. Google can show them in results too. See the lesson on site architecture.
- Canonical URL: The main version of a page that Google chooses to show when several URLs have the same or very similar content. You can suggest it with a canonical tag. See how canonical tags work.
- Citation (local): A mention of your business name, address and phone number on another site, such as a directory. Consistent citations support local SEO. See reviews and citations.
- Click-through rate (CTR): The share of people who saw your result and clicked it. 10 clicks from 200 impressions is a 5% CTR. See how to use Google Search Console.
- Core Web Vitals: Google’s three metrics for real-world page experience: loading (LCP), responsiveness (INP) and visual stability (CLS). See the Core Web Vitals lesson.
- Crawl budget: Roughly how many URLs Google can and wants to crawl on your site. It mainly matters for very large sites. See the technical SEO audit lesson.
- Crawling: The process of search engine bots visiting pages and downloading their content, mostly by following links and sitemaps. See how search engines work.
- Cumulative Layout Shift (CLS): A Core Web Vital that measures how much things on a page jump around while it loads. See Core Web Vitals explained.
SEO terms from D to H
- Digital PR: Creating stories, data or expert comment that journalists want to cover, which earns mentions and links from news sites. See the lesson on digital PR.
- Disavow: A Search Console tool for telling Google to ignore certain links to your site. Most sites never need it. See toxic links and the disavow tool.
- Domain authority: A score created by SEO tool companies to estimate a site’s link strength. It is not a Google metric, and Google doesn’t use it. See what makes a quality link.
- Duplicate content: The same or very similar content at more than one URL. It is usually handled with canonical tags, not punished. See the duplicate content lesson.
- E-E-A-T: Experience, expertise, authoritativeness and trustworthiness: the qualities Google looks for in reliable content. Trust matters most. It is not a single ranking score. See the lesson on E-E-A-T.
- Ecommerce SEO: SEO for online stores, including category pages, product pages, filters and product structured data. See ecommerce SEO basics.
- Featured snippet: A highlighted answer taken from a web page, shown near the top of some search results. See the lesson on the search results page.
- Generative engine optimization (GEO): Work aimed at getting your brand mentioned or cited in AI-generated answers, from Google’s AI features to chat assistants. See generative engine optimization.
- Google Business Profile: Google’s free business listing that appears in Maps and the local results. It shows your hours, reviews, photos and contact details. See the Google Business Profile lesson.
- Google Search Console: Google’s free tool that shows how your site performs in Search: searches, clicks, indexing problems and more. See the Search Console lesson.
- Googlebot: The name of Google’s web crawler, the program that fetches pages for Google Search. See how crawling works.
- Heading tags: The H1 to H6 tags that structure a page into sections, like chapter titles in a book. See headings and page structure.
- Helpful content: Google’s term for content made mainly to help people, not mainly to attract search visits. See the lesson on helpful content.
- Hreflang: A code attribute that tells Google about the different language or country versions of a page. See the international SEO lesson.
- HTTPS: The secure version of HTTP, shown by the padlock in the browser. It encrypts data between the visitor and your site. See HTTPS and site security.
SEO terms from I to L
- Impressions: The number of times your page appeared in search results, whether or not anyone clicked. See reading Search Console data.
- Indexing: When Google processes a crawled page and stores it in its index, the huge database it pulls results from. Only indexed pages can rank. See the indexing lesson.
- Interaction to Next Paint (INP): The Core Web Vital for responsiveness: how quickly a page reacts after you click or tap. It replaced First Input Delay (FID) in March 2024. See Core Web Vitals explained.
- Internal link: A link from one page on your site to another page on the same site. Internal links help visitors and crawlers find your content. See internal linking.
- JavaScript SEO: Making sure content that depends on JavaScript can still be crawled, rendered and indexed by search engines. See the JavaScript SEO lesson.
- Keyword: A word or phrase people type or speak into a search engine. In SEO, keywords are the searches you want a page to appear for. See keyword research basics.
- Keyword cannibalization: When several of your own pages target the same search and compete with each other. See the keyword mapping lesson.
- Keyword difficulty: A tool’s estimate of how hard it would be to rank for a keyword. Each tool calculates it differently. See keyword metrics explained.
- Keyword mapping: Assigning each important keyword (or group of keywords) to one page, so every page has a clear job. See how to map keywords to pages.
- KPI: A key performance indicator: a number you track to judge success, such as organic leads or sales. See the lesson on SEO KPIs.
- Largest Contentful Paint (LCP): The Core Web Vital for loading: how long the biggest visible element, often a main image or heading, takes to appear. See the Core Web Vitals lesson.
- Link building: The work of earning links from other websites to yours, ideally because your content deserves them. See link building strategies.
- Local pack: The group of map-based business listings that appears for local searches like “dentist near me.” See local SEO basics.
- Long-tail keyword: A longer, more specific search with fewer searches each month, such as “waterproof hiking boots for wide feet.” Often easier to rank for. See the lesson on long-tail keywords.
SEO terms from M to R
- Manual action: A penalty applied by a Google reviewer when a site breaks Google’s spam policies. It is reported in Search Console. See white hat vs black hat SEO.
- Meta description: A short summary of a page in its code. Google may show it as the snippet under your title in results. See how to write meta descriptions.
- Mobile-first indexing: Google mainly uses the mobile version of a site’s content for indexing and ranking. See mobile-first indexing.
- Nofollow: A link attribute (rel="nofollow") that tells search engines not to pass credit through a link. Related values are “sponsored” for paid links and “ugc” for user content. See the link quality lesson.
- Noindex: A rule, placed in a meta tag or HTTP header, that tells search engines not to show a page in results. See how indexing works.
- Off-page SEO: Everything outside your own site that affects how it is seen, such as links, mentions and reviews. See the off-page SEO lesson.
- On-page SEO: Optimizing the content and code of individual pages: titles, headings, content, images and internal links. See title tags, the first on-page lesson.
- Organic search: The unpaid results in a search engine, as opposed to ads. SEO is about earning organic visibility. See what SEO is.
- PageRank: Google’s original method of using links to judge a page’s importance. It is still one signal among many. See how Google ranks pages.
- Rank tracking: Recording where your pages appear for chosen keywords over time. See the rank tracking lesson.
- Redirect (301): Sending visitors and search engines from one URL to another. A 301 redirect signals a permanent move. See the redirects lesson.
- Rich results: Search results with extra features such as star ratings, prices or event dates, often made possible by structured data. See structured data and rich results.
- Robots.txt: A text file at the root of your site that tells crawlers which areas they may or may not crawl. See the robots.txt lesson.
SEO terms from S to Z
- Schema markup: Another name for structured data based on the Schema.org vocabulary. See the structured data lesson.
- Search intent: The goal behind a search: to learn something, find a site, compare options or buy. See the lesson on search intent.
- Search volume: An estimate of how many times a keyword is searched in a month. Tools give estimates, not exact counts. See keyword metrics.
- SERP: Short for search engine results page: everything you see after you search, from ads and AI answers to links and maps. See the search results page lesson.
- Site architecture: How the pages of your site are organized and linked together, from the home page down. See site architecture.
- Site migration: A big change to a site, such as a new domain, platform or URL structure, that can affect rankings if handled poorly. See the site migrations lesson.
- Spam policies: Google’s list of practices that can get a site demoted or removed, such as cloaking, keyword stuffing and link spam. See white hat vs black hat SEO.
- Structured data: Code that describes a page’s content in a standard format, for example that a page is a recipe with a cooking time. See how to use structured data.
- Technical SEO: Making sure search engines can crawl, render and index your site, and that it loads fast and securely. See the technical SEO audit lesson.
- Title tag: The HTML title of a page. Google often uses it as the clickable headline in results. See how to write title tags.
- Topic cluster: A group of pages on related subtopics, all linked to a main “pillar” page on the broad topic. See the topic clusters lesson.
- URL slug: The part of a web address that identifies a specific page, such as /running-shoes/. See SEO-friendly URLs.
- Video SEO: Helping your videos get found in search, through clear titles, descriptions, thumbnails and video structured data. See the video SEO lesson.
- White hat SEO: SEO that follows search engine guidelines and focuses on real value for users. See white hat vs black hat SEO.
- XML sitemap: A file that lists the URLs you want search engines to know about. It helps discovery but doesn’t guarantee indexing. See the XML sitemaps lesson.
- YMYL: “Your money or your life”: topics like health, finance and safety, where poor information could seriously harm people. Google holds them to a higher standard. See the E-E-A-T lesson.
- Zero-click search: A search that ends without a click to any website, because the answer is shown on the results page itself. See the search results page lesson.
Try it: translate your own SEO report into plain English
The best way to learn vocabulary is to use it on your own site. Open Google Search Console and work through this checklist. For each term, find where it shows up and write one sentence about what it tells you about your site.
| Term | Where to find it | Question to answer |
|---|---|---|
| Impressions and clicks | Performance report | How many times did my pages appear, and how many people clicked? |
| CTR | Performance report (turn on the CTR box) | Which page has many impressions but a low CTR? |
| Indexing | Page indexing report | How many pages are indexed, and what is the top reason others are not? |
| XML sitemap | Sitemaps report | Is my sitemap submitted and read without errors? |
| Core Web Vitals | Core Web Vitals report | Do any URLs fail LCP, INP or CLS on mobile? |
| Manual action | Manual actions report | Does it say “No issues detected”? |
Then follow these steps:
- Write your six sentences in a document called “My SEO notes.”
- Circle any term you still can’t explain, and open the linked lesson for it above.
- Repeat the exercise next month and compare your notes.
Questions beginners ask about SEO terms
What is the difference between crawling and indexing?
Crawling is Google visiting a page and downloading it. Indexing is Google processing that page and storing it in its index. A page can be crawled but not indexed, and only indexed pages can appear in results.
Are SEO and SEM the same thing?
Not quite. SEO is about earning unpaid, organic visibility. SEM (search engine marketing) is often used for paid search ads, though some people use it to mean both paid and organic search.
Is domain authority a Google ranking factor?
No. Domain authority and similar scores are created by SEO tool companies to estimate link strength. Google does not use them.
Why do SEO terms change so often?
Search itself keeps changing. Terms like AI Overviews, AI Mode and GEO are recent, while metrics like INP replaced older ones such as FID. This course is updated as Google’s documentation changes.
Where this SEO glossary leaves you
You have now covered the full course, and this glossary gives you the words for all of it: how search engines crawl and index pages, how keywords and content match search intent, how links and trust build authority, and how to measure the results. Whenever a term feels fuzzy, come back here and follow the link to its lesson.
If you want to go further, my longer SEO glossary with 100 terms, the AI search glossary and the algorithm update glossary cover more specialist vocabulary. A good next step is to revisit how to build an SEO strategy and put everything into a plan. And if you would like an expert to look at your site with you, you can always request a quote from our team.