SEO Terminology Glossary
The definitive SEO glossary covering 80+ terms from algorithm updates to zero-click searches. Plain-English definitions for beginners and professionals.
SEO has its own language. This glossary provides clear, concise definitions for the most important SEO terms. Use it as a reference as you work through the documentation.
- This glossary covers 80+ SEO terms organised alphabetically.
- Each definition is written in plain English — no jargon to explain jargon.
- Use this page as a reference companion while reading other documentation in this knowledge base.
- Terms link to their relevant in-depth documentation where available.
If you want the full glossary, continue below.
How to Use This Glossary
Terms are organised alphabetically. Use your browser's search function (Ctrl+F / Cmd+F) to jump directly to a specific term.
A
Algorithm — The set of rules and calculations Google uses to determine which pages to rank for a given search query. Google updates its algorithm thousands of times per year.
Alt Text — Descriptive text added to images in HTML that tells search engines (and screen readers) what the image depicts. Important for image SEO and accessibility.
Anchor Text — The visible, clickable text of a hyperlink. Google uses anchor text as a signal to understand what the linked page is about.
Authority — A measure of how trusted and respected a website or page is in its field. Built through backlinks, content quality, and brand reputation. See E-E-A-T.
B
Backlink — A link from another website pointing to yours. Backlinks are one of the strongest ranking signals. Quality matters more than quantity.
Black Hat SEO — SEO practices that violate Google's guidelines, such as link schemes, keyword stuffing, and cloaking. Can result in penalties or deindexing.
Bounce Rate — The percentage of visitors who leave a page without interacting. Note: Google has confirmed that Google Analytics bounce rate is not a ranking factor.
Breadcrumbs — Navigation elements showing the page's position within the site hierarchy (e.g., Home > Resources > SEO > Foundations). Helpful for users and search engines.
C
Canonical Tag — An HTML tag (rel="canonical") that tells Google which version of a page is the preferred one when duplicate or similar versions exist.
Click-Through Rate (CTR) — The percentage of people who click on your search result after seeing it. Calculated as (clicks ÷ impressions) × 100.
Cloaking — Showing different content to search engines than to users. A black hat practice that violates Google's guidelines.
Content Decay — The gradual decline in a page's rankings and traffic over time as content becomes outdated and competitors publish newer material.
Core Update — A significant, broad change to Google's ranking algorithm that can materially affect search results across many topics and industries. See Google Algorithm Updates.
Core Web Vitals — Three standardised metrics measuring page experience: LCP (Largest Contentful Paint), INP (Interaction to Next Paint), and CLS (Cumulative Layout Shift).
Crawl Budget — The number of pages Googlebot will crawl on your site within a given timeframe. Primarily a concern for very large sites (10,000+ pages).
Crawling — The process by which search engine bots discover web pages by following links. See How Search Engines Work.
CLS (Cumulative Layout Shift) — A Core Web Vital measuring visual stability — how much page elements shift during loading. Good score: under 0.1.
D
DA (Domain Authority) — A third-party metric (created by Moz) predicting how likely a domain is to rank. Not used by Google, but useful for competitive analysis.
Disavow File — A file submitted to Google requesting it ignore specific backlinks. Used when toxic or spammy links point to your site and cannot be removed.
Domain Rating (DR) — Ahrefs' metric measuring the strength of a website's backlink profile on a 0–100 scale.
Duplicate Content — Substantially identical content appearing at multiple URLs. Can cause indexation issues as Google chooses one version and ignores others.
E
E-E-A-T — Experience, Expertise, Authority, and Trust. Google's framework for evaluating content quality. See E-E-A-T Explained.
F
Featured Snippet — A highlighted box at the top of some search results showing a direct answer extracted from a web page. Also called "position zero."
Freshness — A ranking signal for certain queries where up-to-date content is important. Queries about current events, pricing, or recent developments favour fresh content.
G
Google Business Profile (GBP) — A free business listing on Google that appears in Maps and local search results. Essential for local SEO. See Local SEO.
Google Search Console (GSC) — A free tool from Google that shows how your site performs in search results. Reports on indexing, rankings, clicks, and technical issues.
Googlebot — Google's web crawler that discovers and indexes web pages by following links across the internet.
H
Heading Tags (H1–H6) — HTML tags used to structure content hierarchically. H1 is the main page heading, H2 for sections, H3 for subsections, and so on.
HTTPS — The secure version of HTTP, using SSL/TLS encryption. A confirmed ranking signal. All modern websites should use HTTPS.
Hreflang — An HTML attribute telling Google which language and regional version of a page to show to users in different countries.
I
Impressions — The number of times your page appeared in search results, whether or not it was clicked.
Index / Indexation — The process of Google adding a web page to its searchable database. Only indexed pages can appear in search results.
Internal Link — A hyperlink from one page on your website to another page on the same website. Critical for distributing authority and helping users navigate.
INP (Interaction to Next Paint) — A Core Web Vital measuring responsiveness — how quickly the page responds to user interactions. Good score: under 200ms.
K
Keyword — A word or phrase that users type into search engines. SEO involves optimising pages to rank for specific keywords.
Keyword Cannibalisation — When multiple pages on the same site compete for the same keyword, splitting ranking signals and reducing performance.
Keyword Difficulty (KD) — A metric estimating how hard it would be to rank on page 1 for a specific keyword. Higher scores indicate more competition.
Keyword Mapping — The process of assigning specific target keywords to individual pages on your site to avoid overlap and cannibalisation.
Keyword Stuffing — Unnaturally repeating keywords in content to manipulate rankings. A black hat practice that Google penalises.
L
LCP (Largest Contentful Paint) — A Core Web Vital measuring loading performance — how long the main content element takes to load. Good score: under 2.5 seconds.
Link Building — The process of acquiring backlinks from other websites to increase your site's authority. See Link Building.
Link Equity — The SEO value passed from one page to another through a hyperlink. Also called "link juice." Internal and external links both pass equity.
Local Pack / Map Pack — The map and three business listings that appear for local search queries (e.g., "plumber near me").
Long-Tail Keyword — A longer, more specific search phrase (e.g., "affordable web designer for small business in Pretoria" vs "web designer"). Lower volume but higher conversion rates.
M
Meta Description — A brief summary of a page's content displayed under the title in search results. Not a direct ranking factor but influences click-through rate.
Meta Keywords — An HTML tag listing keywords relevant to the page. Google has ignored this tag since 2009. It has no ranking value.
Mobile-First Indexing — Google's practice of using the mobile version of a page for indexing and ranking. All websites are now evaluated mobile-first.
N
NAP (Name, Address, Phone) — The three critical pieces of business information that must be consistent across all online listings for local SEO.
Nofollow — A link attribute (rel="nofollow") that tells search engines not to pass link equity through that link.
Noindex — A directive telling search engines not to include a specific page in their index. Used for private pages, duplicate content, or thin pages.
O
Organic Traffic — Website visitors who arrive through unpaid search results. The primary goal of SEO.
P
Page Experience — Google's overall assessment of how users experience a web page, including Core Web Vitals, mobile-friendliness, HTTPS, and absence of intrusive interstitials.
PageRank — Google's original algorithm for measuring page importance based on the quantity and quality of backlinks. While Google no longer publishes PageRank scores, link-based authority remains a core ranking signal.
PBN (Private Blog Network) — A network of websites created solely to build backlinks to a target site. A black hat practice that Google penalises.
People Also Ask (PAA) — A SERP feature showing related questions and answers. Optimising for PAA can increase visibility beyond the traditional top 10 results.
Position Zero — The featured snippet at the top of search results, above the #1 organic result.
R
Ranking — The position of a page in search results for a specific query. "Ranking #3 for 'web design Johannesburg'" means appearing third in organic results.
Robots.txt — A text file at the root of your website that tells search engine crawlers which pages they may or may not access.
Rich Result — An enhanced search result that includes extra visual information (ratings, images, prices, FAQs) generated from structured data markup.
S
Schema Markup — Code (usually JSON-LD) added to web pages that helps search engines understand the content better. Enables rich results in search. See Structured Data & Schema Markup.
Search Intent — The purpose behind a search query — what the user actually wants to accomplish. See Understanding Search Intent.
SERP (Search Engine Results Page) — The page Google displays in response to a search query, containing organic results, ads, featured snippets, and other features.
Sitemap — An XML file listing all important pages on your site, submitted to search engines to aid discovery and crawling.
Structured Data — Machine-readable code that helps search engines understand the content and context of a page. See Schema Markup.
T
Technical SEO — The practice of optimising a website's infrastructure for search engine crawling, indexing, and rendering. See Technical SEO.
Title Tag — The HTML <title> element defining the page's title. Displayed as the clickable headline in search results. One of the most important on-page ranking signals.
Topical Authority — The degree to which a website is recognised as an authoritative source on a specific topic, built through comprehensive, interlinked content.
U
URL — Uniform Resource Locator. The web address of a page. Clean, descriptive URLs are preferred for both SEO and usability.
User Experience (UX) — How users interact with and feel about a website. Google evaluates UX signals including page speed, mobile-friendliness, and layout stability.
W
White Hat SEO — SEO practices that comply with Google's guidelines and focus on long-term, sustainable results.
Y
YMYL (Your Money, Your Life) — Topics that could significantly impact a person's health, finances, safety, or well-being. Google applies higher quality standards to YMYL content.
Z
Zero-Click Search — A search where the user gets their answer directly on the results page (e.g., from a featured snippet, knowledge panel, or AI overview) without clicking any result.
Key Takeaways
- SEO has a specialised vocabulary. Understanding these terms makes all documentation in this knowledge base easier to follow.
- Bookmark this page as a reference companion for your SEO learning journey.
- Pay special attention to terms marked with links — they connect to in-depth documentation on those topics.
Tools & Resources (Coming Soon)
- SEO Audit Tool (Coming soon)
- Keyword Difficulty Checker (Coming soon)
- Schema Markup Generator (Coming soon)
Related SEO Documentation
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