Domain Investing Glossary
Domain investing has four decades of accumulated jargon: registry lifecycle terms written by engineers, auction slang written by traders, and marketplace vocabulary invented by whichever platform got there first. Knowing the difference between a backorder and a drop catch — or a lander and a parked page — is table stakes for operating in this market.
This glossary defines each term the way investors actually use it, with the registry-policy details where they matter and links to deeper guides where a definition is not enough.
Registry & Registration
Registrar
A registrar is the ICANN-accredited company where you register and manage domains. How registrars differ from registries, and why the split matters.
Registry
A registry is the organization that operates a TLD's authoritative database — like Verisign for .com. How registries set prices and lifecycle rules.
Registrant
The registrant is the person or entity that holds a domain registration — the owner of record. Registrant vs. registrar, and why the details matter.
TLD
A TLD is the last label of a domain name — .com, .ai, .io. The main TLD types, who operates them, and why TLD choice drives price and lifecycle rules.
ccTLD
A ccTLD is a two-letter country code TLD like .ai, .io, or .de. Why ccTLDs follow their own rules, and what that means for pricing and expiry risk.
gTLD
A gTLD is a generic top-level domain like .com, .net, or .app, operated under ICANN contract. What the shared gTLD rulebook means for domain investors.
New gTLD
New gTLDs are the extensions launched through ICANN's 2012 program — .app, .xyz, .dev and hundreds more. What investors should know before holding them.
SLD
An SLD is the second-level domain — the part directly left of the TLD, like example in example.com. Why the SLD carries nearly all of a domain's value.
Hand Registration
Hand registration means registering an available domain at the standard fee, rather than buying it in the aftermarket. Where hand-reg value still hides.
Premium Domain
Premium domain means two things: a registry-priced name costing more than base rate, or a high-value aftermarket name. Why the renewal fine print matters.
Reserved Domain
A reserved domain is withheld from registration by the registry or ICANN policy — not owned, not premium, just unavailable. How reserved names get released.
Domain Transfer
A domain transfer moves a name from one registrar to another using an auth code. The standard steps, the 60-day locks, and the free year most transfers add.
Domain Push
A domain push moves a name between two accounts at the same registrar — instant, usually free, no auth code. How pushes differ from full registrar transfers.
WHOIS Privacy
WHOIS privacy replaces your public registration contact data with a proxy service's details. What it hides, what GDPR changed, and when to turn it off.
Technical
WHOIS
WHOIS is the legacy protocol for looking up domain registration data — owner, dates, statuses. Why RDAP replaced it for gTLDs and what still uses it.
RDAP
RDAP is the Registration Data Access Protocol — the structured, JSON-based successor to WHOIS and the authoritative way to read gTLD domain records.
EPP
EPP is the protocol registrars use to create, renew, and transfer domains at the registry — and the source of status codes like clientTransferProhibited.
Nameserver
A nameserver is the DNS server that answers queries for a domain's records. How delegation works and what nameservers reveal about a domain's use.
DNSSEC
DNSSEC adds cryptographic signatures to DNS so resolvers can verify records are authentic. How it works, and the transfer gotcha investors should know.
Registrar Lock
A registrar lock is the standard registrar-level transfer lock on a domain, shown as clientTransferProhibited. How it differs from a registry lock.
Registry Lock
A registry lock freezes a domain at the registry itself, requiring manual out-of-band verification to change anything. Who needs it and what it costs.
Auth Code
An auth code is the per-domain password required to transfer a domain between registrars — also called an EPP code or transfer key. How to get and use one.
IDN / Punycode
IDNs are domains using non-ASCII characters; Punycode is the xn-- encoding that makes them work in DNS. How they trade and the homograph risk to know.
DNS Propagation
DNS propagation is the delay before a DNS change is seen everywhere, driven by resolver caches honoring TTL values. What really happens and how to speed it up.
Lifecycle & Drops
Grace Period
The grace period is the window after expiry when you can still renew a domain at the normal price — typically 0-45 days at the registrar's discretion.
Redemption Fee
A redemption fee is the extra charge to recover a domain from the redemption period after expiry — typically $70-$200 on top of the renewal price.
Drop
A drop is the moment a deleted domain is released by the registry and becomes available to register again. How the drop works and who competes for it.
Drop Catching
Drop catching is the automated race to register a domain the instant the registry deletes it. How catching services work and how auctions decide winners.
Backorder
A backorder is a standing request for a drop-catching service to grab a domain the moment it deletes. Costs, auctions, and multi-service strategy.
Expired Domain
An expired domain has passed its paid-through date but is not yet deleted. The stages between expiry and the drop, and what each means for buyers and owners.
Aged Domain
An aged domain has years of registration history, prized for backlinks, trust, and SEO carryover. What age really signals and how buyers verify it.
Auto-Renew
Auto-renew tells your registrar to charge your card and renew a domain before expiry. Why it silently fails, and the backup layers investors add.
Buying & Selling
Domainer
What a domainer is: an investor who buys, holds, and sells domain names as assets. How domainers make money, and how they differ from cybersquatters.
Domain Investing
Domain investing explained: buying domain names as assets, how the portfolio model works, commonly cited sell-through rates, and the records to keep.
Domain Flipping
What domain flipping means: buying domain names and reselling them quickly, often at wholesale prices to other investors, versus long-hold investing.
Domain Parking
Domain parking explained: pointing unused domains at ad or for-sale placeholder pages, how parking revenue works, and why landers often beat parked ads.
Parked Page
What a parked page is: the placeholder shown on a registered but undeveloped domain — registrar defaults, PPC ads, or for-sale banners — and what it signals.
Lander
What a lander is in domain sales: a for-sale landing page on an undeveloped domain, showing a BIN price or offer form, built to convert type-in visitors.
BIN Price
What a BIN price is: a fixed buy-it-now price on a domain listing that lets a buyer purchase instantly without negotiation, and when to use one.
Make Offer
What a make-offer listing is: a domain for sale without a posted price, where buyers submit offers and the seller negotiates. When it beats a fixed BIN.
Domain Broker
What a domain broker does: negotiating domain purchases or sales on a client's behalf for a commission — buyer brokers, seller brokers, stealth deals.
Domain Marketplace
What a domain marketplace is: a platform for listing, buying, and selling domains, with search, checkout, escrow-style settlement, and typical commissions.
Aftermarket
What the domain aftermarket is: the secondary market where already-registered domains are resold — marketplaces, auctions, brokers — vs new registration.
Domain Auction
What a domain auction is: competitive bidding for domains, from expired-domain auctions at registrars to seller-listed auctions on marketplaces.
End User
What an end user is in domain sales: a buyer who wants the domain to actually use for a business or project — and why end users pay retail prices.
Reseller Price
What reseller price means: the wholesale value a domain fetches from other investors, versus end-user retail — and why the gap between them is so large.
Outbound Sales
What outbound sales means in domaining: proactively contacting likely end users to pitch a domain, instead of waiting for inbound buyers to find it.
Inbound Inquiry
What an inbound inquiry is: an unsolicited message from a potential buyer about your domain — why it signals real demand and how to handle one well.
Lease-to-Own
How lease-to-own domain deals work: the buyer pays monthly and takes ownership after the final payment, with the domain held by a platform in between.
Domain Escrow
What domain escrow is: a neutral third party holds the buyer's payment until the domain transfers, protecting both sides of an aftermarket sale.
Valuation & Metrics
Domain Appraisal
What a domain appraisal is: an estimate of a domain's market value from comps, keyword demand, length, and TLD — and why estimates vary so widely.
Comps
What comps are in domain investing: recorded sales of similar domains used to estimate value and set prices, where to find them, and their blind spots.
Liquidity
What liquidity means for domains: how quickly a name converts to cash near its value. Why most domains are illiquid and which categories trade fastest.
Sell-Through Rate
What sell-through rate means for a domain portfolio: the share of names that sell per year, commonly cited 1-2% benchmarks, and how STR drives pricing.
Cost Basis
What cost basis means for a domain: acquisition price plus renewals and fees paid to hold it — the number real profit is measured against at sale time.
Renewal Drag
What renewal drag is: the cumulative annual renewal cost of holding a domain portfolio, silently eroding returns — and how investors cut it each year.
Legal & Disputes
UDRP
What the UDRP is: ICANN's policy for resolving trademark-based domain disputes through providers like WIPO and Forum, and the three elements to prove.
Cybersquatting
What cybersquatting is: registering domains that target someone else's trademark in bad faith, how it differs from domain investing, and the remedies.
Typo Domain
What a typo domain is: a common misspelling of another domain, registered to catch mistyped traffic — and why typos of trademarks are a legal hazard.
Domain Types
Exact-Match Domain
What an exact-match domain is: a domain that exactly matches a search query, like cheapflights.com — its history in SEO and what EMDs are worth now.
Keyword Domain
What a keyword domain is: a name built from commercially valuable search terms, like insurance.com — how keyword value is judged and priced by investors.
Brandable Domain
What a brandable domain is: an invented or evocative name chosen for sound and memorability rather than keywords — and how brandables are valued and sold.
Numeric Domain
What a numeric domain is: a name made entirely of digits, like 888.com — why number length and digit patterns drive value, and who buys numeric names.
LLL Domain
What an LLL domain is: a three-letter domain like IBM.com — only 17,576 exist per TLD, all LLL .coms are long registered, and why they trade like a commodity.
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