Domain Glossary — Industry Terms

The complete domain glossary — DNS, TLDs, EPP, WHOIS, schema, drop catching, brandability and 80+ more terms explained simply.

Domains

Domain Name: A human-readable address (e.g. namesale.store) that maps to an IP address, letting people reach a website without memorizing numbers.
TLD (Top-Level Domain): The final segment of a domain name, like .com, .io, or .ai. TLDs are managed by registries and influence trust and SEO.
ccTLD: Country-code top-level domain — two-letter TLDs tied to a country (e.g. .us, .uk, .de). Used for local targeting.
gTLD: Generic top-level domain like .com, .net, .org — not tied to a country, broadest reach.
Subdomain: A prefix added to a root domain (blog.example.com). Used for sections, microsites, or product lines.
Premium Domain: A short, memorable, brandable, or keyword-rich domain commanding above-registration pricing — typically $100 to $1M+.
Hyphenated Domain: A domain using dashes (best-pizza.com). Generally weaker than non-hyphenated for trust and recall.
IDN (Internationalized Domain Name): Domain containing non-ASCII characters (e.g. café.com). Encoded as Punycode in DNS.
WHOIS: Public protocol/database showing registration information (registrar, dates, sometimes contact) for a domain.

DNS

DNS: Domain Name System — the internet's phonebook, translating names like google.com into IP addresses.
Nameserver: Server that holds DNS records for a domain (e.g. ns1.cloudflare.com). Points the domain to its hosting.
A Record: DNS record mapping a domain (or subdomain) to an IPv4 address.
AAAA Record: DNS record mapping a domain to an IPv6 address.
CNAME Record: Canonical-name record that aliases one domain to another (www → root domain).
MX Record: Mail-exchange record specifying the mail servers responsible for receiving email for a domain.
TXT Record: Free-form text record used for domain verification, SPF, DKIM, and other validations.
TTL: Time-to-Live — how long a DNS record may be cached. Lower TTL means faster propagation but more queries.
DNS Propagation: The time (minutes to 48 hours) for DNS changes to spread across resolvers worldwide.
DNS A Record: Maps a hostname to an IPv4 address. The most common DNS record type for pointing a domain to a web server.
DNS CNAME: Canonical Name record — aliases one hostname to another. Used to point subdomains at platforms like Vercel or Shopify.
DNS MX Record: Mail Exchange record — directs email for a domain to the correct mail server. Required for custom-domain email.
DNS TXT Record: Free-form text record used for verification (SPF, DKIM, domain ownership) rather than routing traffic.
SPF Record: TXT record listing which mail servers are authorized to send email for your domain. Reduces spoofing and improves deliverability.
DKIM: DomainKeys Identified Mail — cryptographic email signature stored as a DNS record, proving the sender controls the domain.
DMARC: DNS-published policy that tells receivers what to do with email that fails SPF/DKIM checks. Critical for inbox deliverability.

Registry

Registrar: ICANN-accredited company (GoDaddy, Namecheap, Dynadot) where end users register and manage domains.
Registry: The organization that operates a TLD's master database (e.g. Verisign for .com, PIR for .org).
Registrant: The person or entity that legally owns a domain registration.
EPP Code: Authorization code (also called transfer secret) required to move a domain between registrars.
ICANN: Internet Corporation for Assigned Names and Numbers — coordinates global domain name and IP address systems.
Domain Transfer: Moving a domain registration from one registrar to another. Typically takes 5-7 days and requires the EPP code.
Push Transfer: Internal account-to-account move at the same registrar — instant, no EPP needed. Common at Dynadot/GoDaddy.
Auto-Renew: Setting that automatically renews a domain before expiration to prevent accidental loss.
Grace Period: Window (usually 30 days) after expiration when the original owner can still renew without extra fees.
Redemption Period: Phase after the grace period (about 30 days) when a domain can still be recovered, but with a steep restoration fee.
Pending Delete: Final 5-day phase before an expired domain returns to the public pool for re-registration.
UDRP: Uniform Domain-Name Dispute-Resolution Policy — the ICANN process trademark owners use to reclaim infringing domains.
ACPA: Anticybersquatting Consumer Protection Act — US federal law allowing damages against bad-faith registrants of trademarked domains.
Renewal Grace Period: 30-45 day window after a domain expires during which the owner can still renew at standard pricing.
Redemption Period: Roughly 30-day post-grace window when an expired domain can be redeemed only by the original owner, for a high fee.
Pending Delete: Final 5-day phase before an expired domain returns to general availability. Triggers drop-catching activity.

SEO

Exact Match Domain (EMD): A domain that exactly matches a target search query (bestpizza.com). Past SEO advantage; today brand strength matters more.
Domain Authority (DA): Moz's 0-100 score predicting how likely a domain is to rank. Higher is better; built largely from backlinks.
Domain Rating (DR): Ahrefs' equivalent to DA — 0-100 measure of a domain's backlink profile strength.
Backlink: An inbound link from another website — a primary trust signal for search engine ranking.
Anchor Text: The clickable visible text of a hyperlink. Influences what search engines associate with the destination.
Canonical URL: The preferred version of a URL when duplicates exist. Set via <link rel="canonical"> to consolidate ranking signals.
301 Redirect: Permanent HTTP redirect that passes nearly all link equity to the new URL.
302 Redirect: Temporary HTTP redirect — does not consolidate ranking signals as fully as a 301.
Sitemap.xml: XML file listing a site's important URLs to help search engines discover and crawl them efficiently.
Robots.txt: Plain-text file at /robots.txt telling crawlers which paths to allow or disallow.
Schema Markup: Structured data (typically JSON-LD) describing page content so search engines can show rich results.
Domain Authority (DA): Moz's 0-100 score predicting how well a domain will rank in search. Influenced by backlinks, content, and age.
Page Authority (PA): Moz's per-page ranking-strength metric, scaled 0-100. Tighter to actual SERP performance than DA.
Backlink: An inbound link from another site. The primary off-page SEO signal — quality and relevance matter more than raw count.
Anchor Text: The visible, clickable text of a hyperlink. Influences which keywords a target page ranks for.
Referring Domain: A unique domain that contains at least one backlink to your site. More referring domains generally beats more raw backlinks.
Canonical URL: The preferred URL for a page when duplicate or near-duplicate versions exist. Set via <link rel='canonical'>.
Sitemap: An XML file listing the indexable pages on a site, helping search engines discover and prioritize crawling.
Robots.txt: Plain-text file at /robots.txt instructing search crawlers which paths they may or may not access.
Schema Markup: Structured data (typically JSON-LD) added to pages so search engines can render rich results like FAQs and breadcrumbs.

Investing

Drop Catching: The practice of registering a desirable domain the instant it returns to the public pool after expiry.
Aged Domain: Domain registered for many years. Sometimes carries SEO history and trust — though only if cleanly used.
Expired Domain: A domain whose registration lapsed. May be re-registered for its existing backlinks and traffic.
Domain Investing: Buying domains with the intent to resell at a profit. Sometimes called domain flipping.
Domain Flipping: Short-cycle buy-and-resell of domains — typically at a 3x-30x markup.
Reserve Price: Minimum acceptable price an auction must clear for a sale to complete.
BIN (Buy It Now): Fixed price at which a domain can be purchased instantly without negotiation or auction.
Make Offer: Listing where buyers submit bids and sellers negotiate — common for higher-value names.
End User: A buyer purchasing a domain to actually use (build a brand) rather than resell. Pays the highest prices.
Wholesale Price: Price between domain investors — typically far below end-user retail.
Retail Price: Final asking price for end users — premium over wholesale, accounts for marketing and curation.
Liquid Domain: A domain (commonly LLLL.com or NN.com) with consistent demand and predictable price ranges.
LLL.com: Three-letter .com domain — historically among the most liquid asset classes in domains.
NNNN.com: Four-number .com — high liquidity, especially with Asian buyers; pricing follows pattern desirability.
Comp (Comparable Sale): A recent sale of a similar domain used as a pricing reference. Sourced from NameBio, DNJournal.
STR (Sell-Through Rate): Percentage of a portfolio that sells per year — a key ROI metric for domain investors.
Renewal ROI: The ratio of expected revenue per name vs annual renewal cost. Below 1.0 means a renewal trim is wise.
Lander: A simple landing page on a for-sale domain showing price and contact form. Captures inbound demand.
Domain Squatting: Registering a domain matching a trademark or brand to resell at a markup. Legally risky under UDRP and the ACPA.
Backorder: A service that attempts to register a domain the moment it expires and becomes available. Used to catch dropped premium names.
Drop Catching: Automated registration of expiring domains the instant they're released by the registry. Highly competitive for valuable names.
Aftermarket: The secondary market for already-registered domains, sold by current owners rather than directly by the registry.
Comparable Sales (Comps): Recent sale prices of similar domains used to value a name. The single most reliable input for domain appraisal.
Appraisal: An estimate of a domain's market value, based on length, TLD, keyword strength, brandability, and comparable sales.
Domain Parking: Hosting a placeholder ad-supported page on an unused domain to generate small click revenue while it sits for sale.
Drop List: The published list of domains scheduled to expire and drop back to general availability on a given day.
Reserve Price: The minimum price a seller will accept in an auction or negotiation, often kept hidden from buyers.
Buy It Now (BIN): A fixed price at which a domain can be purchased immediately without negotiation. Standard on marketplaces.
Make Offer: A listing type where buyers submit bids and sellers can accept, counter, or decline. Common for non-BIN inventory.
Lease-to-Own: A purchase structure that splits a domain's cost into monthly payments, transferring ownership after the final installment.

Security

WHOIS Privacy: Service that masks personal contact data in WHOIS with the registrar's proxy details.
Domain Lock: Status (clientTransferProhibited) preventing unauthorized transfers — should stay enabled until you intentionally move.
SPF Record: TXT record listing servers authorized to send email on behalf of your domain — reduces spoofing.
DKIM: DomainKeys Identified Mail — cryptographic email signing that proves a message wasn't altered in transit.
DMARC: Policy layer over SPF/DKIM telling receivers what to do with failing mail (none, quarantine, reject).
DNSSEC: DNS Security Extensions — digitally signs DNS records to prevent spoofing and cache poisoning.
SSL/TLS Certificate: Cryptographic certificate enabling HTTPS — encrypts traffic between browser and server.
Domain Hijacking: Unauthorized takeover of a domain — usually via compromised registrar account or social engineering.
Cybersquatting: Registering a domain matching a trademark to extort the rightful owner. Actionable under UDRP.
Typosquatting: Registering misspelled variants (gooogle.com) to capture mistyped traffic — often for ads or phishing.
UDRP: Uniform Domain-Name Dispute-Resolution Policy — ICANN process for trademark holders to recover infringing domains.
Cybersquatting: Bad-faith registration of a domain identical or confusingly similar to a registered trademark — actionable under UDRP.
Typosquatting: Registering common misspellings of popular domains (gooogle.com) to capture mistyped traffic. Often violates trademark law.

Branding

Brandable Domain: An invented or evocative name (Stripe, Lyft, Notion) built for trademark and recall rather than literal meaning.
Trademark: Legally registered word, phrase, or symbol identifying goods/services. Critical to clear before naming a brand.
USPTO: United States Patent and Trademark Office — primary US trademark registry to search before buying a domain.
Brandability: Subjective measure of how distinctive, memorable, and trademarkable a name is — a top driver of premium pricing.
Mnemonic: Memory device — short, rhythmic, vowel-balanced names (Uber, Zara) score high on mnemonic strength.
Phonetic Spelling: Spelling that matches pronunciation (Lyft vs Lift). Trade-off: distinctive but may need explanation.
CVCV Pattern: Consonant-vowel-consonant-vowel name pattern (e.g. Loka, Rivo) — easy to say globally, premium for naming.

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