SEO Glossary: 200+ A-Z

Search engine optimization has its own language, and if you don’t speak it, everything else feels harder than it should.

This SEO glossary is built to fix that.

Inside, you’ll find 200+ essential SEO terms explained in plain English, organized alphabetically so you can quickly find what you need. 

Whether you’re trying to understand technical SEO concepts like crawl budget and indexing, content and keyword terms like topical authority and search intent, or modern topics such as AI search optimization and entity SEO, this glossary gives you clear, one-sentence explanations without jargon.

Use it as a reference guide, a learning resource, or a quick refresher while auditing sites, writing content, or planning SEO strategies. It’s designed for beginners who want clarity and professionals who want precision.

A

1. Above the Fold – The portion of a webpage visible to users before they scroll.
   
   
2. AI Citations – References AI systems use to support or validate generated answers.
   
   
3. AI Overviews – AI-generated summaries that appear directly in search results.
   
   
4. AI Search Optimization – Optimizing content to surface in AI-powered search experiences.
   
   
5. Algorithm – A system search engines use to rank and order search results.
   
   
6. Algorithmic Penalty – A ranking drop caused automatically by an algorithm update.
   
   
7. Algorithm Update – A change to how search engines evaluate and rank content.
   
   
8. Alt Text – Text describing an image for accessibility and search engines.
   
   
9. AMP – A framework that improves mobile page loading speed.
   
   
10. Analytics – Tools that measure website traffic and user behavior.
    
    
11. Anchor Text – The clickable text within a hyperlink.
    
    
12. Answer Engine Optimization – Optimizing content to directly answer questions in AI and search engines.
    
    
13. Authority – The perceived trust and credibility of a website or page.
    
    
14. Authority Site – A website widely trusted and referenced within its industry.
    
    

B

1. Backlink – A link from another website pointing to your site.
   
   
2. Black Hat SEO – SEO tactics that violate search engine guidelines.
   
   
3. Bounce Rate – The percentage of users who leave after viewing one page.
   
   
4. Brand Authority – The strength and trust of a brand in search results.
   
   
5. Brand Search – A query that includes a brand name.
   
   
6. Branded Anchor – Anchor text that contains a brand name.
   
   
7. Breadcrumbs – Navigation links showing a page’s position in site hierarchy.
   
   
8. Broken Link – A link that leads to a non-existent or error page.
   
   

C

1. Canonical URL – The preferred version of a page when duplicates exist.
   
   
2. Citation – An online mention of a business’s name, address, and phone number.
   
   
3. Click Depth – The number of clicks needed to reach a page from the homepage.
   
   
4. Click-Through Rate (CTR) – The percentage of impressions that result in clicks.
   
   
5. Cloaking – Showing different content to search engines and users.
   
   
6. Content Audit – An evaluation of existing content performance and quality.
   
   
7. Content Authority Score – A measure of content trustworthiness and expertise.
   
   
8. Content Cluster – Interlinked content pages centered around a main topic.
   
   
9. Content Decay – The gradual decline in content performance over time.
   
   
10. Content Velocity – The rate at which new content is published.
    
    
11. Conversion Rate – The percentage of users who complete a desired action.
    
    
12. Core Web Vitals – Metrics measuring page speed, responsiveness, and stability.
    
    
13. Crawl Budget – The number of pages a search engine crawls on a site.
    
    
14. Crawl Error – An issue preventing a page from being crawled.
    
    
15. Crawl Path – The route search engines follow when crawling a website.
    
    
16. Crawler – A bot that discovers and scans web pages.
    
    

D

1. Data Layer – A structured data source used for analytics and tracking.
   
   
2. Disavow Tool – A Google tool for rejecting harmful backlinks.
   
   
3. Domain Authority – A predictive score estimating domain ranking strength.
   
   
4. Dofollow Link – A link that passes SEO value.
   
   
5. Duplicate Content – Identical or highly similar content across URLs.
   
   
6. Dynamic URL – A URL generated with parameters.
   
   

E

1. E-E-A-T – Google’s framework for expertise, experience, authoritativeness, and trustworthiness.
   
   
2. Edge SEO – SEO changes implemented via CDN without server access.
   
   
3. Engagement Rate – A measure of how users interact with content.
   
   
4. Entity SEO – Optimizing content around identifiable entities instead of keywords.
   
   
5. Entity Salience – The importance of an entity within content.
   
   
6. Evergreen Content – Content that remains relevant long-term.
   
   
7. Exact Match Domain – A domain name that exactly matches a keyword.
   
   
8. External Link – A link pointing to another website.
   
   

F

1. Featured Snippet – A highlighted answer shown above organic results.
   
   
2. Featured Snippet Optimization – Optimizing content to appear in featured snippets.
   
   
3. First Input Delay – A Core Web Vital measuring interaction responsiveness.
   
   
4. Footer Links – Links placed in a webpage footer.
   
   
5. Freshness – How recently the content was updated.
   
   

G

1. Geo-Targeting – Delivering content based on geographic location.
   
   
2. Google Algorithm – Google’s system for ranking search results.
   
   
3. Google Business Profile – A tool for managing local business visibility.
   
   
4. Google Sandbox – A theorized delay affecting new site rankings.
   
   
5. Google Search Console – A tool for monitoring site performance in Google Search.
   
   
6. Gray Hat SEO – SEO tactics between ethical and unethical practices.
   
   

H

1. Header Hierarchy – The structured use of heading tags.
   
   
2. Heading Tags (H1–H6) – HTML elements organize content structure.
   
   
3. Historical Optimization – Updating older content to improve performance.
   
   
4. Hreflang – A tag specifying language and regional targeting.
   
   
5. HTML Sitemap – A user-facing page listing site URLs.
   
   
6. HTTPS – A secure version of HTTP.
   
   

I

1. Image SEO – Optimizing images for search visibility.
   
   
2. Impression – When a page appears in search results.
   
   
3. Index – A database of stored web pages.
   
   
4. Index Bloat – Excess low-value pages indexed.
   
   
5. Index Latency – Delay between publishing and indexing.
   
   
6. Index Saturation – Percentage of pages indexed by search engines.
   
   
7. Indexing – The process of storing pages in search databases.
   
   
8. Information Gain – The uniqueness and added value of content.
   
   
9. Informational Intent – Searches made to learn information.
   
   
10. Inbound Link – Another term for a backlink.
    
    
11. Internal Linking – Links between pages on the same website.
    
    

J

1. JavaScript SEO – Optimizing JavaScript-heavy websites for crawling and indexing.
   
   

K

1. Keyword – A word or phrase users search for.
   
   
2. Keyword Cannibalization – Multiple pages competing for the same keyword.
   
   
3. Keyword Density – Keyword frequency within content.
   
   
4. Keyword Research – Finding and analyzing search terms.
   
   
5. Keyword Stuffing – Excessive keyword use to manipulate rankings.
   
   
6. Knowledge Graph – Google’s entity-based knowledge database.
   
   
7. Knowledge Panel – An information box displayed in search results.
   
   

L

1. Landing Page – A page designed to convert visitors.
   
   
2. Latent Semantic Indexing (LSI) – Contextually related terms.
   
   
3. Link Building – Acquiring backlinks to improve rankings.
   
   
4. Link Equity – SEO value passed through links.
   
   
5. Link Gap Analysis – Identifying links competitors have but you don’t.
   
   
6. Link Velocity – The rate of backlink acquisition.
   
   
7. Local Pack – Map-based local search results.
   
   
8. Local SEO – Optimizing for location-based searches.
   
   
9. Log File Analysis – Reviewing server logs to understand crawling.
   
   
10. Long-Tail Keyword – A longer, more specific keyword phrase.
    
    
11. LLM.txt – A file guiding large language model access.
12. LLM Visibility – How often does content appear in AI answers?
    
    

M

1. Manual Action – A penalty applied by Google reviewers.
   
   
2. Manual Outreach – Actively requesting backlinks.
   
   
3. Meta Description – A page summary shown in search results.
   
   
4. Meta Robots Tag – Instructions controlling indexing behavior.
   
   
5. Mobile-First Indexing – Google ranking based on mobile versions.
   
   
6. Mobile Usability – How well a site works on mobile devices.
   
   
7. Multimodal Search – Search using text, images, or voice.
   
   
8. Multi-Location SEO – SEO for businesses with multiple locations.
   
   

N

1. NAP – Consistent name, address, and phone information.
   
   
2. Natural Language Processing – AI understanding of human language.
   
   
3. Natural Link – An organically earned backlink.
   
   
4. Negative SEO – Attempts to harm a site’s rankings.
   
   
5. Noindex – A directive preventing page indexing.
   
   
6. Nofollow – A link attribute blocking link equity.
   
   

O

1. Off-Page SEO – SEO actions outside the website.
   
   
2. On-Page SEO – Optimizing content and HTML.
   
   
3. Organic Keyword – A keyword driving unpaid traffic.
   
   
4. Organic Traffic – Traffic from unpaid search results.
   
   
5. Orphan Page – A page with no internal links.
   
   
6. Outbound Link – A link pointing to another site.
   
   

P

1. Page Authority – Ranking strength of an individual page.
   
   
2. Page Depth – Distance of a page from the homepage.
   
   
3. Page Experience – Signals measuring user satisfaction.
   
   
4. PageRank – Google’s original link-based authority metric.
   
   
5. Page Speed – How fast a page loads.
   
   
6. Pagination – Dividing content across multiple pages.
   
   
7. Parasite SEO – Ranking content on third-party platforms.
   
   
8. Passage Indexing – Ranking individual content sections.
   
   
9. People Also Ask – Related questions shown in SERPs.
   
   
10. Pillar Page – A central page supporting related content.
    
    
11. Programmatic SEO – Automated creation of SEO pages.
    
    
12. Prompt-Based Search – Search driven by conversational prompts.
    
    

Q

1. Query – A search phrase entered by a user.
   
   
2. Query Deserves Freshness – Queries favoring recent content.
   
   
3. Query Fan-Out – Expanding a query into multiple variations.
   
   
4. Query Intent Matching – Aligning content with search intent.
   
   
5. Query Refinement – Modifying queries for better results.
   
   

R

1. RankBrain – Google’s AI system interpreting search queries.
   
   
2. Rank Tracking – Monitoring keyword positions over time.
   
   
3. Ranking Factor – A signal influencing search rankings.
   
   
4. Reciprocal Link – Mutual linking between sites.
   
   
5. Redirect (301) – A permanent URL redirect.
   
   
6. Referring Domain – A unique site linking to yours.
   
   
7. Relative URL – A URL without a domain name.
   
   
8. Retrieval-Augmented Generation – AI responses generated using external data.
   
   
9. Rich Results – Enhanced SERP listings with extra features.
   
   
10. Robots.txt – A file controlling crawler access.
    
    

S

1. Sales Funnel SEO – SEO aligned with buyer journey stages.
   
   
2. Schema Markup – Structured data for search engines.
   
   
3. Search Demand – Interest level for a search query.
   
   
4. Search Ecosystem – The complete search environment.
   
   
5. Search Experience Optimization – Improving search-driven user journeys.
   
   
6. Search Generative Experience – Google’s AI-based SERP format.
   
   
7. Search Intent – The purpose behind a query.
   
   
8. Search Personalization – Results tailored to user behavior.
   
   
9. Search Trust Layer – Signals verifying content reliability.
   
   
10. Search Visibility – How often a site appears in search.
    
    
11. Search Visibility Index – A metric measuring overall SERP presence.
    
    
12. Semantic SEO – Optimizing for meaning, not just keywords.
    
    
13. SEO Audit – A comprehensive SEO evaluation.
    
    
14. SEO Moat – A defensible competitive SEO advantage.
    
    
15. SERP – Search engine results page.
    
    
16. SERP Features – Enhanced result elements beyond blue links.
    
    
17. SERP Volatility – Fluctuations in search rankings.
    
    
18. Site Architecture – How pages are organized.
    
    
19. Sitewide Link – A link appearing across many pages.
    
    
20. Slug – The readable part of a URL.
    
    
21. Spam Link – A low-quality or manipulative backlink.
    
    
22. Spam Score – A metric estimating link risk.
    
    
23. Split Testing – Comparing variations for performance.
    
    
24. Static URL – A fixed URL without parameters.
    
    
25. Structured Data – Machine-readable content markup.
    
    
26. Subdomain – A subsection of a main domain.
    
    
27. Syndicated Content – Content republished on other sites.
    
    

T

1. Taxonomy – Content classification structure.
   
   
2. Technical SEO – Optimizing backend infrastructure.
   
   
3. Thin Content – Low-value or shallow content.
   
   
4. Time on Page – How long users stay on a page.
   
   
5. Title Tag – The clickable SERP headline.
   
   
6. Topical Authority – Depth of expertise on a topic.
   
   
7. Topical Map – A structured topic-based content plan.
   
   
8. Topical Relevance – How closely content match a topic?
   
   
9. Traffic – Visitors to a website.
   
   
10. Transactional Intent – Searches aimed at completing an action.
    
    
11. Trust Signals – Elements that build credibility.
    
    

U

1. Universal Search – Results combining multiple content types.
   
   
2. Unnatural Link – A manipulative backlink.
   
   
3. URL Structure – Organization of URLs.
   
   
4. User Experience (UX) – How users interact with a site.
   
   
5. User Signals – Behavioral data influencing rankings.
   
   

V

1. Vertical Search – Search within a specific category.
   
   
2. Vertical SEO – SEO tailored to an industry.
   
   
3. Viewport – The visible area of a webpage.
   
   
4. Voice Search – Searches performed using speech.
   
   

W

1. Web Crawling – Discovering and scanning web pages.
   
   
2. Web Spam – Manipulative content created to game rankings.
   
   
3. Web Vitals – Metrics measuring real-world page performance.
   
   
4. Website Silos – Topic-based content grouping.
   
   
5. Whitelist – Approved sources or links.
   
   
6. White Hat SEO – Ethical SEO practices.
   
   

X

1. XML Sitemap – A file listing URLs for search engines.
   
   

Z

1. Zero-Click Search – Searches answered without a website click.
   
   
2. Zero-Search Volume Keyword – A keyword with demand but no reported volume.

Conclusion

SEO changes fast, but the fundamentals behind these terms still power rankings, traffic, and visibility.

This glossary isn’t meant to be read once and forgotten. Bookmark it. Come back when a term feels fuzzy. Link to it from your blog posts, service pages, and internal documentation. 

The better you understand the language of SEO, the easier it becomes to spot problems, explain strategies to clients, and make smarter optimization decisions.

If you’re serious about building long-term search visibility, mastering these concepts is not optional. It’s the baseline.

And once the terminology clicks, the strategy becomes much easier.