AI SEO

SEO Glossary: Search Terms Explained Plainly

16 September 2026 9 min read
Short answer

This SEO glossary defines the terms used across search engine optimisation, grouped into search basics, technical SEO, on-page SEO, content and semantics, links and authority, local SEO, AI search, and measurement. Each definition is written plainly, so a business owner can follow an agency report or audit without a specialist background.

What Do the Common SEO Terms Actually Mean?

SEO has an unusually large amount of jargon, and much of it is used loosely. That makes reports harder to read than they need to be.

This glossary defines the terms you are most likely to meet in an audit, a proposal or a monthly report, grouped by the area they belong to.

Skim the group you need rather than reading top to bottom. If a term you are looking for is missing, it is probably covered in the introduction to SEO.

Key takeaways

  • Most SEO terms describe one of three things: access, meaning, or trust.
  • Crawling, indexing and ranking are separate stages that fail separately.
  • Intent describes what a searcher wants, and decides what page type can rank.
  • AEO, GEO and AIO describe visibility in generated answers rather than blue links.
  • Authority is earned through links, citations and brand mentions, not bought.
  • Impressions, clicks and conversions measure different things — never one alone.

Search basics

Core search terminology
TermDefinition
SEOImproving a website so it earns visibility in unpaid search results.
SERPSearch engine results page — everything shown for a query, ads included.
Organic resultAn earned listing you do not pay per click for.
Paid resultAn advertising slot bought through an auction such as Google Ads.
QueryThe words someone actually types or says into a search engine.
KeywordA phrase a page is intended to rank for.
Search intentWhat the searcher is trying to achieve: learn, compare, buy or navigate.
Long-tail queryA longer, more specific search with lower volume and clearer intent.
Head termA short, broad, high-volume and usually highly competitive phrase.
Branded queryA search containing your business name.
Non-branded queryA search with no brand name, showing new demand.
Featured snippetAn answer box quoting a page above the standard results.
People Also AskThe expandable related questions shown within a results page.
Map packThe local results block showing businesses and a map.
Zero-click searchA search resolved on the results page without a visit to any site.

Technical SEO terms

How search engines access a site
TermDefinition
CrawlingA search engine following links to discover pages.
IndexingStoring and understanding a crawled page so it can be shown.
Crawl budgetThe effective limit on how much of a site gets crawled in a period.
robots.txtA file telling crawlers which paths they may request.
noindexAn instruction telling search engines not to include a page.
Canonical tagA signal naming the preferred version of duplicate or similar pages.
Redirect (301)A permanent forward from one URL to another, passing most signals.
Redirect (302)A temporary forward, which should not be used for permanent moves.
Status codeThe server's response: 200 works, 404 missing, 500 error.
XML sitemapA file listing the URLs you want crawled and indexed.
Core Web VitalsGoogle's measures of loading, interaction and visual stability.
LCPLargest Contentful Paint — when the main content becomes visible.
CLSCumulative Layout Shift — how much the page moves while loading.
RenderThe process of executing a page's code to see final content.
JavaScript SEOMaking content built by scripts reliably crawlable and indexable.
Log file analysisReviewing server records of what crawlers actually requested.
Structured dataMachine-readable markup describing a page's contents.
Schema markupThe vocabulary used for structured data, usually in JSON-LD.
HreflangMarkup indicating language and regional targeting of pages.
Site architectureHow pages are grouped and linked to each other.

On-page SEO terms

What sits on the page itself
TermDefinition
Title tagThe clickable headline shown in results, usually under 60 characters.
Meta descriptionThe summary beneath the title, influencing clicks rather than rank.
H1The main on-page heading describing what the page is.
H2 / H3Subheadings that structure sections and sub-questions.
URL slugThe readable part of the address identifying the page.
Alt textA description of an image for screen readers and search engines.
Internal linkA link from one page of your site to another.
Anchor textThe visible words used for a link.
Keyword cannibalisationTwo pages competing for the same query, splitting signals.
Content depthHow completely a page resolves the question it targets.
Above the foldContent visible before the reader scrolls.
Thin contentA page with too little substance to satisfy the query.
Duplicate contentSubstantially identical content across multiple URLs.
Orphan pageA page with no internal links pointing to it.

Content and semantic terms

How meaning is understood
TermDefinition
Semantic SEOOptimising for meaning and relationships rather than exact phrases.
EntityA distinct thing — person, place, brand, concept — that engines recognise.
Knowledge graphA database of entities and how they relate to each other.
Topical authorityRecognised depth of coverage across a subject area.
Pillar pageA broad page covering a topic and linking to detailed subpages.
Content clusterA pillar page plus supporting articles interlinked around one topic.
E-E-A-TExperience, expertise, authoritativeness and trust — quality signals.
Content decayGradual loss of visibility as content becomes outdated.
Content refreshUpdating an existing page rather than publishing a new one.
Search journeyThe sequence of searches someone makes while deciding.

Local SEO terms

Visibility in a place
TermDefinition
Local SEOOptimising to appear for searches tied to a place.
Google Business ProfileThe listing controlling map pack and knowledge panel details.
NAP consistencyMatching name, address and phone number across the web.
Service areaThe geographic area a business states that it covers.
ProximityHow close the searcher is to the business — a strong local factor.
ProminenceHow well known and well reviewed a business appears to be.
Local pack rankingPosition within the map results for a local query.
Review velocityThe rate at which new reviews arrive over time.
Location pageA page targeting a specific town or area you serve.

Measurement terms

How results are reported
TermDefinition
ImpressionsHow often your pages appeared for searches.
ClicksVisits earned from those impressions.
CTRClick-through rate — clicks divided by impressions.
Average positionThe mean ranking position across recorded impressions.
ConversionA tracked valuable action such as a form submission or call.
Search ConsoleGoogle's free tool reporting queries, coverage and indexing.
AttributionAssigning credit for a conversion across channels.
Share of voiceYour visibility for a keyword set relative to competitors.
BaselineThe recorded starting point used to judge later change.

For how these fit together in practice, see the guide to the types of SEO or our SEO services.

Frequently asked questions

What is the difference between SEO, AEO and GEO?+

SEO earns visibility in traditional results. AEO aims to be the direct answer to a question. GEO aims to be referenced inside AI assistant responses. The underlying fundamentals overlap heavily.

Is domain authority a Google ranking factor?+

No. It is a third-party estimate produced by SEO tools. Useful as a rough comparison between sites, but Google does not use or publish it.

What does E-E-A-T actually mean?+

Experience, expertise, authoritativeness and trust — the qualities Google's raters use to judge content quality. It is not a direct score, but it describes what the algorithms try to approximate.

Which metric matters most?+

Conversions, followed by non-branded impressions as a leading indicator. Average position is the least useful of the common metrics because it varies by device, location and personalisation.

Do I need to know all of this?+

No. Understanding crawling, indexing, intent, internal links and conversions is enough to hold a competent conversation with any agency and to spot vague reporting.

Using this glossary

Keep this page to hand when reading an audit or proposal. If a document uses terms it never explains, that is usually a sign the work behind it has not been explained either.

A good agency will define its terms without being asked, and tie each one to something it intends to change on your site.

If you would like a plain-English review of your current SEO, get in touch.

Related reading

Turn AI search visibility into measurable pipeline.

A short review shows where your site is already close to being cited, and what to fix first.