Glossary — 25 terms · A-Z order

SEO Glossary 2026. The 25 terms agencies sell you smoke with if you don't get them.

The fastest way to be sold SEO that doesn't work is by using terms you don't understand. Here they are, explained for what they are — and why they matter to you. For each term: what it is, why it matters, what to demand from your vendor.

A

  • Algorithm

    Algoritmo / Search Algorithm

    What it is

    The system of rules Google uses to rank pages. Not a single algorithm but a layered stack: index, ranking signals, intent matching. Changes with monthly Core Updates and continuous tweaks (helpful content).

    Why it matters

    A sudden traffic variation is almost always linked to an algorithm update. Without monitoring update dates + traffic, you attribute to luck what is engine mechanics.

    What to demand

    Dashboard cross-referencing algorithm update timeline (Search Engine Roundtable, Semrush Sensor) with organic traffic. Without it, every SEO discussion is opinion.

  • Anchor Text

    Testo del link

    What it is

    The clickable text of a link. Example: web design services has anchor 'web design services'. Google uses the anchor to understand what the linked page is about.

    Why it matters

    Uniform anchors like "click here" don't help Google contextualise. Over-optimised anchors (exactly the target keyword on every link) are a spam signal.

    What to demand

    Natural anchor mix: brand (Calicchia Design), exact keyword (web design Frosinone). Keyword variation (Ciociaria website), naked URL (calicchia.design), generic (here, article). 30/20/20/15/15 average distribution.

B

  • Bounce Rate

    Frequenza di rimbalzo

    What it is

    Percentage of users who leave the site without interaction (in classic UA). In GA4 it's replaced by 'engagement rate' (complementary): a user is 'engaged' if they stay >10s, view ≥2 pages, or trigger a conversion event.

    Why it matters

    High bounce on a landing page = intent match problem (user wanted something else) or UX (mobile-unreadable site). Suspect intent first, then UX.

    What to demand

    Engagement rate >55% for target landing pages. Below, debug: is the copy off-intent? is the design unreadable? is LCP at 5s scaring people away? Never decorative fix, always causal.

C

  • Canonical

    URL canonical / rel="canonical"

    What it is

    HTML tag that tells Google "this page is a duplicate of X, index X". Resolves duplicate content from URL parameters (utm_), paginated pages, separate mobile/desktop.

    Why it matters

    Wrong canonical = Google indexes the wrong page, you lose ranking on the canonical you thought was strong. Missing canonical = Google picks alone, often wrong.

    What to demand

    Every page has an explicit canonical. Duplicate pages (e.g. /products?color=red) point to /products. Canonical audit via Screaming Frog on every major release.

  • Crawl Budget

    What it is

    Number of pages the Google bot crawls on your site per visit. Determined by: server speed, site popularity, content freshness. Large sites (>10k pages) are limited; small sites are not.

    Why it matters

    On large sites, wasting crawl budget on useless pages (infinite e-commerce filters, calendars, paginated archives) means important pages don't get crawled.

    What to demand

    robots.txt blocking useless patterns (?sort=, ?filter=). XML sitemap with only indexable pages. Fast server (<200ms TTFB) and strategic internal links.

  • Core Web Vitals

    CWV — LCP, CLS, INP

    What it is

    Three Google metrics for UX quality: LCP (Largest Contentful Paint, <2.5s), CLS (Cumulative Layout Shift, <0.1), INP (Interaction to Next Paint, <200ms). Ranking signal since 2021.

    Why it matters

    Red CWV = ranking downgrade. For e-commerce, every 100ms more LCP = -1% conversions. It's not "nice to have", it's a qualifier to play the SEO game.

    What to demand

    Green CWV on CrUX field data (75% real users). Monthly monitoring via PageSpeed Insights API. Immediate alerts on any technical regression.

D

  • Domain Authority

    DA / DR — Moz / Ahrefs

    What it is

    Score 0-100 computed by Moz (DA) or Ahrefs (DR) that proxies a domain's authority. It is NOT an official Google metric — it's a private estimate. Useful for benchmark, not decisions.

    Why it matters

    Agencies selling SEO with 'we'll raise your DA' are selling numerical gymnastics, not ranking. High DA correlates with ranking but doesn't cause it.

    What to demand

    Focus on outcome metrics: organic traffic, conversion, page 1 ranking. DA/DR are vanity metrics for agencies without results. DA is just a competitor benchmark.

E

  • E-E-A-T

    Experience, Expertise, Authoritativeness, Trustworthiness

    What it is

    Google framework for quality raters: Experience (does the author have direct experience?), Expertise (are they competent?), Authoritativeness (are they recognised as a source?), Trustworthiness (are they reliable?). Critical for YMYL (Your Money Your Life).

    Why it matters

    Without strong E-E-A-T, content on health, finance, legal, food is structurally penalised. Author bio, credentials, authoritative links are real ranking factors.

    What to demand

    Detailed author bio (Person schema). Authoritative external citations and case studies with real data. No AI-generated content without human review.

F

G

  • Google Search Console

    GSC

    What it is

    Google's free tool showing how your site performs in search results: queries driving traffic, CTR, average position, indexing errors, manual actions.

    Why it matters

    Without GSC you are blind on SEO. Analytics tells you users+sessions, but not what they searched to arrive. GSC is the truth on Google's side.

    What to demand

    GSC verified with DNS TXT, sitemap submitted, weekly monitoring on top-50 queries, email alert on manual action. Performance API export for BigQuery analysis beyond 16 months.

H

  • Hreflang

    What it is

    HTML tag that tells Google which language/region version of a page to serve based on user location/language. Example: it, en, en-us, en-gb, x-default.

    Why it matters

    Wrong hreflang = IT user sees EN page, EN user sees IT page. High bounce rate, lost conversions. On multi-locale sites it's the most common bug.

    What to demand

    Reciprocal hreflang (IT links EN, EN links IT), x-default for fallback, audit via GSC International Targeting. If the site has /it /en, no IP-based redirect (Google penalises it).

I

  • Index / Indexing

    Indicizzazione

    What it is

    Inclusion of a page in the Google database. A page can be crawled (visited by the bot) but not indexed (not stored). Without indexing, it doesn't appear in results.

    Why it matters

    Non-indexed pages = pages that don't exist for Google. Common causes: noindex tag, robots.txt crawl block, thin/duplicate content, low quality signal.

    What to demand

    GSC Indexing report monitored weekly. All target pages "Indexed". "Crawled - currently not indexed" = symptom of quality issue, debug per page.

K

  • Keyword

    Parola chiave

    What it is

    Word or phrase users type into Google to find content. Categorised by: search volume, difficulty (KD), intent (informational/navigational/transactional/commercial).

    Why it matters

    Wrong keyword research = you write content nobody searches for. High volume + high difficulty = impossible for small sites. Long-tail (3+ words) = low volume but high intent, conversion-friendly.

    What to demand

    Keyword tracking GSC + Semrush/Ahrefs on top 20-50 target keywords. Mix: head terms (volume) + long-tail (intent). Never target a DR>40 keyword with a DR<20 site.

L

M

  • Meta Description

    What it is

    HTML tag describing the page content in 150-160 characters. Not a direct ranking factor, but influences SERP CTR (and CTR is an indirect ranking factor).

    Why it matters

    Empty meta description = Google generates a random one from content, often poor. Duplicate descriptions across 100 pages = negative quality signal.

    What to demand

    Unique description per page, 140-160 characters, naturally includes target keyword, proposes clear CTA ("Discover", "Compare"). Meta audit via Screaming Frog every release.

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