SEO conversations are packed with acronyms and shorthand that nobody explains before using. This SEO glossary defines the terms and acronyms you'll actually run into, from SERP to E-E-A-T, in plain English, with links to a deeper guide wherever we've written one. Bookmark it; we'll keep it updated.
Search & Ranking Basics
SEO (Search Engine Optimization), the practice of improving a site so it ranks higher in organic search results. New to the concept? Start with our SEO 101 beginner's guide.
SERP (Search Engine Results Page), the page of results a search engine shows for a query. See our full breakdown of what SERPs are and how SERP features work.
SEM (Search Engine Marketing), the umbrella term covering both organic SEO and paid search advertising.
KD (Keyword Difficulty), a score estimating how hard it is to rank in the top 10 for a given keyword.
SERP Features, non-standard results like featured snippets, People Also Ask boxes, local packs, and AI Overviews that appear above or beside normal listings.
On-Page & Content Terms
On-Page SEO, optimizing the elements on a page itself: titles, headers, content and internal links. Full breakdown in our on-page SEO checklist.
Title Tag, the clickable headline shown in search results and browser tabs. See our guide to writing SEO title tags that rank and get clicked.
Meta Description, the short summary shown under a title tag in search results; doesn't directly affect rankings but strongly affects click-through rate.
E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness), Google's framework for judging content quality, especially critical for YMYL (Your Money or Your Life) topics like the ones we cover in medical and healthcare SEO.
Content Decay, the gradual drop in rankings and traffic that older content experiences as it goes stale; we cover the fix in our piece on content decay defense.
Keyword Cannibalization, when two or more pages on the same site compete for the same keyword, splitting ranking signals instead of combining them.
Technical SEO Terms
Crawling, the process by which search engine bots discover pages by following links.
Indexing, storing a crawled page's content in a search engine's database so it can be returned in results.
Core Web Vitals, Google's set of page-experience metrics (loading speed, interactivity, visual stability) used as ranking signals; part of our complete technical SEO guide.
Canonical Tag, an HTML tag that tells search engines which version of a duplicate or similar page should be treated as the "master" copy.
XML Sitemap, a file listing a site's important URLs, submitted through Google Search Console to help search engines find and prioritize pages.
Schema Markup, structured data added to a page's code that helps search engines understand its content and can unlock rich results.
Off-Page & Link Building Terms
Backlink, a link from another website pointing to yours; still one of the strongest off-page ranking signals. Learn how to check yours in our guide to auditing your backlink profile.
Dofollow Link and Nofollow Link, attributes that tell search engines whether to pass ranking credit through a link. Full explanation in nofollow vs dofollow links.
Anchor Text, the clickable, visible text of a hyperlink.
Negative SEO, malicious tactics aimed at damaging a competitor's rankings, such as spam link attacks. See what negative SEO is and how to defend against it.
Parasite SEO, publishing content on a high-authority third-party domain to rank quickly instead of building your own site's authority; we explain the risks in what is parasite SEO.
Digital PR, earning backlinks and brand mentions through press coverage and outreach rather than direct link requests.
Local, International & AI Search Terms
Local SEO, optimizing a business's visibility for geographically relevant searches. Full playbook in our local SEO for small business guide.
GBP (Google Business Profile), the free listing that controls how a business appears in Google Maps and the local pack; see how to improve your Google Business Profile ranking.
International SEO, the practice of optimizing a site to rank correctly across multiple countries or languages; explained in what is international SEO.
AI Overview, Google's AI-generated summary shown above traditional results for many queries.
GEO (Generative Engine Optimization), the emerging practice of optimizing content to be cited by AI answer engines like ChatGPT, alongside traditional SEO. See our guide to ranking in Google, ChatGPT and AI search.
Strategy & Measurement Terms
SEO Audit, a full review of a site's technical health, content and backlinks to find what's holding rankings back. Use our SEO audit checklist and template to run your own.
Content Strategy, the plan behind what to publish, in what order, and why, built around topical clusters rather than one-off posts. See our SEO content strategy guide.
Topical Authority, the degree to which a search engine trusts a site as a comprehensive source on a subject, built by covering a topic in depth across multiple connected pages.
Organic Traffic, visitors who arrive at a site through unpaid search results, as opposed to paid ads or referrals.
FAQ
What does KD mean in SEO?
KD stands for Keyword Difficulty, a score used to estimate how hard it would be to rank on page one for a given search term.
What is the difference between SEO and SEM?
SEO refers specifically to organic, unpaid rankings. SEM is the broader category that includes both SEO and paid search advertising.
What does E-E-A-T stand for?
Experience, Expertise, Authoritativeness and Trustworthiness, the framework Google's quality raters use to judge content, especially on topics that affect health, finances or safety.
Still running into a term we haven't covered? Ask Rafenthic's team and we'll add it.