This glossary defines 78 terms you will run into when finding, vetting, buying, and using expired domains, from registry lifecycle stages and EPP status codes to backlink metrics and Google spam policies. Terms are listed alphabetically. Each entry links to the guide that covers the topic in depth.

0–9

301 Redirect

An HTTP status code meaning a URL has moved permanently to a new location. Search engines generally consolidate ranking signals to the destination, which is why 301s are used to pass an expired domain's link equity to relevant pages. 301 Redirects →

302 Redirect

An HTTP status code for a temporary move. Google may eventually treat a long-standing 302 like a 301, but for permanent moves a 301 states the intent clearly. 301 Redirects →

404 Not Found

The HTTP status returned when a URL doesn't exist. 404s are normal and don't harm the rest of a site, but backlinks pointing at a 404 page pass no value. Post-Acquisition Checklist →

410 Gone

An HTTP status indicating a URL has been removed intentionally and permanently. Search engines drop it from the index much like a 404, possibly slightly faster. It's useful for clearing spam URLs left by a previous owner. Post-Acquisition Checklist →

A

Add Grace Period

A short window, typically 5 days after a new gTLD registration, during which the registrar can delete the domain and get the registry fee refunded. ICANN fee changes in 2008 curbed its abuse for domain tasting. Domain Lifecycle Guide →

Aftermarket

The secondary market where already-registered domains are bought and sold between owners, through marketplaces, brokers, and auction platforms, as opposed to registering an available name at standard price. Flipping & Reselling →

Anchor Text

The visible, clickable text of a hyperlink. In backlink analysis, an anchor profile dominated by exact-match commercial phrases or foreign-language spam terms is a red flag. Backlink Analysis →

Auction

A competitive bidding sale of a domain. In the expired market this usually means an expiry auction run by a registrar's partner platform, or a backorder auction when several people backorder the same dropping name. Auctions vs. Closeouts vs. Drops →

Authority Score

Semrush's 0–100 domain-level metric combining link power, organic traffic estimates, and spam signals. Like all third-party scores, it is not used by Google. Semrush review →

B

A link from another website to yours. For expired domains, backlinks are often the main source of value, so their quality, relevance, and live status are central to vetting. Backlink Analysis →

Backorder

A request placed with a drop-catching service to try to register a domain the moment it is deleted. You usually pay only if the catch succeeds, and multiple backorders on one name typically lead to an auction. Backorders & Drop Catching →

Brandable Domain

A short, memorable, often invented name (not a keyword phrase) chosen for its value as a brand. Brandables are judged more on sound and length than on SEO metrics. Domain Valuation →

C

ccTLD

A country-code top-level domain such as .uk, .de, or .ca. Each ccTLD's registry sets its own expiry, deletion, and transfer rules, which can differ significantly from gTLD rules. Domain Lifecycle Guide →

CDX API

The Internet Archive's Wayback Machine capture index API (web.archive.org/cdx/search/cdx). It lists archived URLs with timestamps, status codes, and MIME types, and is used to recover an old site's URL structure. Rebuilding from the Archive →

Citation Flow

Majestic's 0–100 metric estimating how influential a URL or domain may be based on the quantity of links pointing to it, without regard to quality. It is usually read alongside Trust Flow. Majestic review →

clientHold

An EPP status set by the registrar that removes the domain from the DNS zone, so it stops resolving. It is commonly applied to expired domains during the grace period, and also for non-payment or abuse. Domain Lifecycle Guide →

Cloaking

Showing search engines different content from what users see, for example serving a clean page to Googlebot and spam to visitors. It is a Google spam policy violation, and a cloaked history is a reason to reject an expired domain. Spam Checking →

Closeout

A fixed-price or low-reserve sale of an expired domain that received no bids in its expiry auction, held shortly before the domain would otherwise be released. Auctions vs. Closeouts vs. Drops →

D

Disavow

A Google Search Console tool for asking Google to ignore specific links or linking domains. Google says most sites don't need it. It's mainly relevant after a manual action for unnatural links. Post-Acquisition Checklist →

DNS

The Domain Name System, which maps domain names to IP addresses and other records (MX, TXT, CNAME). Pointing a newly acquired domain's DNS at infrastructure you control is a first-day task. Post-Acquisition Checklist →

DNSSEC

Extensions that cryptographically sign DNS records. A stale DS record left at the registry from a previous owner can make a domain fail to resolve until it is removed or updated. Post-Acquisition Checklist →

Domain Age

Usually the time since a domain was first registered. A domain that dropped and was re-registered typically gets a new creation date in WHOIS. Google has said age by itself is not a ranking factor; history and links matter more. The Vetting Blueprint →

Domain Authority

Moz's 1–100 score predicting how well a domain may rank, based mainly on its link profile. It's a comparative third-party metric, not a Google signal. Backlink Analysis →

Domain Flipping

Buying domains at low cost (often expired names) and reselling them at a profit, usually via marketplaces or direct outreach to end users. Flipping & Reselling →

Domain Rating

Ahrefs' 0–100 logarithmic score of the strength of a domain's backlink profile. Because DR can be inflated with low-quality links, it should be checked against referring domain quality. Ahrefs review →

Domain Tasting

The now-largely-abandoned practice of registering domains in bulk, testing their traffic during the Add Grace Period, and deleting the unprofitable ones for a refund. Domain Lifecycle Guide →

Drop

The moment a domain is deleted from the registry after Pending Delete and becomes available to register again. For many gTLDs, drops happen in a daily batch at a predictable time. Domain Lifecycle Guide →

Drop Catching

Using fast, automated registrar connections to register a domain in the instant it drops. Drop-catch services compete with each other, so popular names usually end in an auction among backorderers. Backorders & Drop Catching →

Drop List

A list of domains scheduled to be deleted soon, usually those in Pending Delete. Sites such as ExpiredDomains.net publish filterable drop lists. ExpiredDomains.net review →

E

EPP Code (Auth Code)

A unique authorization code issued by the current registrar that is needed to transfer a domain to another registrar. Treat it like a password. How to Buy Expired Domains →

EPP Status Codes

Standard statuses defined by the Extensible Provisioning Protocol that describe a domain's state, such as clientTransferProhibited, clientHold, redemptionPeriod, and pendingDelete. They appear in WHOIS and RDAP output. Domain Lifecycle Guide →

Escrow

A neutral third party that holds the buyer's payment until the domain has been transferred, protecting both sides in private aftermarket sales. Flipping & Reselling →

Exact Match Domain

A domain that exactly matches a search query (for example, a keyword phrase plus .com). Google's 2012 EMD update reduced the ranking advantage of low-quality exact-match domains. Domain Valuation →

Expired Domain

A domain whose registration term has ended without renewal. It passes through registrar and registry stages (grace, redemption, pending delete) before being released or sold. Domain Lifecycle Guide →

Expired Domain Abuse

A Google spam policy (added in March 2024) covering expired domains bought and repurposed mainly to manipulate rankings with low-value content, often unrelated to the domain's previous purpose. Rebuilding from the Archive →

Expiry Auction

An auction of a domain during its post-expiration grace period, run by the registrar or its auction partner, before the domain would reach the registry's redemption phase. Auctions vs. Closeouts vs. Drops →

G

Grace Period (Auto-Renew)

The period after expiration during which the registrant can usually still renew at the normal price. Length varies by registrar and TLD; for gTLDs it is often in the range of 0–45 days. Verify with your registrar. Domain Lifecycle Guide →

gTLD

A generic top-level domain such as .com, .net, .org, or newer extensions like .shop. gTLDs follow ICANN policies on expiration, transfer, and deletion. Domain Lifecycle Guide →

H

Hand Registration

Registering an available domain normally at a registrar's standard price, as opposed to buying it at auction, via backorder, or on the aftermarket. How to Buy Expired Domains →

I

ICANN

The Internet Corporation for Assigned Names and Numbers, the non-profit that coordinates the DNS root and sets policies for gTLD registries and accredited registrars, including transfer and expiration rules. Domain Lifecycle Guide →

IndexNow

An open protocol that lets websites notify participating search engines (including Bing and Yandex) instantly when URLs are added, updated, or deleted. Google doesn't use it. Post-Acquisition Checklist →

L

The ranking value a link is thought to pass to the page it points to. It depends on the linking page's authority, relevance, and link attributes, and can be carried through 301 redirects. 301 Redirects →

A group of sites that exist mainly to link to each other or to clients, with little real content. Links from link farms are a spam signal in a domain's backlink profile. Spam Checking →

M

Majestic

A backlink index and toolset known for its Trust Flow, Citation Flow, and Topical Trust Flow metrics. Majestic review →

Manual Action

A penalty applied by a human reviewer at Google when a site violates spam policies. It is reported in Search Console under Security & Manual Actions and can be addressed with a reconsideration request. Google Index & Penalty Check →

Money Site

The primary site you want to rank and earn revenue from, as opposed to supporting sites. Expired domains are sometimes used as the base for a money site. Money Site Creation →

Moz Spam Score

Moz's percentage estimate of how many sites with similar features have been penalized or banned by Google. It indicates risk, not an actual penalty. Spam Checking →

N

NameBio

A public database of reported historical domain sales, widely used to find comparable sales when valuing a domain. Domain Valuation →

Nameserver

The DNS servers authoritative for a domain, set at the registrar. Changing nameservers moves control of all DNS records to a new provider. Post-Acquisition Checklist →

Nofollow

A link attribute (rel="nofollow", alongside rel="sponsored" and rel="ugc") that tells search engines not to associate the link with ranking credit. Google treats these attributes as hints. Backlink Analysis →

P

Parked Domain

A domain that shows a placeholder or ad page rather than a real website. Long parked periods in a domain's history usually mean its old rankings and link value have faded. History & Wayback Machine →

PBN

A private blog network: a set of sites, often built on expired domains, used to link to a money site to manipulate rankings. It violates Google's link spam policies. Private Blog Networks →

Pending Delete

The final, typically 5-day registry status (pendingDelete) after the Redemption Grace Period. The domain can't be renewed or restored and is deleted at the end of it. Pending Delete Domains →

Pre-release

Sale of an expiring domain by the registrar or its partners before it drops, usually during or just after the expiry auction window. The domain is transferred to the buyer without ever being released publicly. Auctions vs. Closeouts vs. Drops →

R

RDAP

The Registration Data Access Protocol, the structured JSON successor to WHOIS for querying domain registration data. ICANN requires gTLD registries and registrars to support it. Domain Lifecycle Guide →

Redemption Grace Period

A registry-level period, typically 30 days for gTLDs, after a domain is deleted by the registrar. Only the previous registrant can restore it, usually for a restore fee on top of renewal. Domain Lifecycle Guide →

Referring Domains

The number of unique domains linking to a site. It is generally a more meaningful measure than total backlinks, since one site can produce thousands of sitewide links. Backlink Analysis →

Registrant

The person or organization that holds the registration of a domain and controls it through the registrar. Trademark & Legal Risk →

Registrar

An organization accredited (by ICANN for gTLDs, or by the relevant ccTLD registry) to sell domain registrations to the public and manage them at the registry. Domain Lifecycle Guide →

Registrar Lock

The clientTransferProhibited status (often with update and delete prohibitions), set at the registrar to block unauthorized transfers. Enable it immediately after acquiring a domain. Post-Acquisition Checklist →

Registry

The organization that operates a TLD's authoritative database and zone (for example, Verisign for .com and .net). Registrars sell names; registries maintain them. Domain Lifecycle Guide →

Registry Lock

Server-level statuses (such as serverTransferProhibited) applied by the registry at a registrar's request. Changes then require manual, out-of-band verification. It's used for high-value domains. Post-Acquisition Checklist →

Restore Fee

A fee charged to recover a domain from the Redemption Grace Period. It varies by registrar and is usually much higher than a normal renewal, so check current pricing. Domain Lifecycle Guide →

S

Scaled Content Abuse

A Google spam policy (March 2024) against producing many pages, by AI, automation, or humans, primarily to manipulate rankings rather than help users. Rebuilding from the Archive →

Search Console

Google's free tool for site owners to monitor indexing, search performance, links, manual actions, and security issues. Verify every newly acquired domain in it. Post-Acquisition Checklist →

Site Reputation Abuse

A Google spam policy against publishing third-party content on a site to exploit that site's ranking signals with little oversight or involvement from the host. Rebuilding from the Archive →

Soft 404

A page that returns a 200 status but looks like an error or empty page to Google. Mass redirects to an irrelevant page, such as the homepage, can also be treated as soft 404s. 301 Redirects →

T

Topical Relevance

How closely a linking site's or domain's subject matches your own. Relevant links and a consistent topical history are generally more valuable and less risky than raw authority. Backlink Analysis →

Topical Trust Flow

Majestic's categorization of Trust Flow by subject (for example, Recreation/Travel), showing which topics a domain's trusted links come from. Majestic review →

A loose term for a link that looks manipulative or spammy. Tools assign toxicity scores, but Google says it ignores most such links automatically. Spam Checking →

Transfer Lock (60-day)

A restriction, under ICANN's Transfer Policy, preventing a gTLD domain from moving to another registrar for 60 days after registration or an inter-registrar transfer (and, depending on registrar, after a change of registrant). How to Buy Expired Domains →

Trust Flow

Majestic's 0–100 metric estimating link quality based on how closely a site is linked to a hand-picked set of trusted seed sites. A Trust Flow far below Citation Flow can indicate low-quality links. Backlink Analysis →

Typosquatting

Registering misspellings of well-known brands or domains to capture mistyped traffic. It carries significant trademark and UDRP risk. Trademark & Legal Risk →

U

UDRP

The Uniform Domain-Name Dispute-Resolution Policy, ICANN's process that lets trademark owners seek transfer of a domain registered and used in bad faith. Panels can order transfers but not award damages. Trademark & Legal Risk →

W

Wayback Machine

The Internet Archive's archive of historical web page snapshots (web.archive.org). It's essential for checking what an expired domain hosted before you buy it. History & Wayback Machine →

WHOIS

The traditional protocol and lookup service for domain registration data (registrar, dates, status, and contacts where not redacted). For gTLDs it is being replaced by RDAP. Domain Lifecycle Guide →

WHOIS Privacy

A registrar service that replaces or redacts the registrant's personal contact details in public registration data. Post-Acquisition Checklist →

Z

Zone File

The registry's file listing every registered domain in a TLD and its nameservers. Access to gTLD zone files is available through ICANN's Centralized Zone Data Service (CZDS), and comparing daily zone files reveals dropped domains. Pending Delete Domains →

Next Steps

Put the vocabulary to work: