The Deliverability Glossary
Master the technical and strategic vocabulary of B2B cold email deliverability.
Glossary Categories
Blacklist / DNSBL
An email blacklist is a public, real-time database of IP addresses and domain names flagged by cybersecurity organizations for sending spam or suspicious bulk traffic.
Read definitionBlocklist
The standardized industry term for an email blacklist, designating a real-time list of IP addresses and domains flagged for abusive sending behavior.
Read definitionCatch-All Email
A catch-all email server is configured to accept all incoming messages sent to its domain, even if the specific recipient address does not exist on the server.
Read definitionData Validation
Data validation is the multi-step verification process that checks whether an email address is authentic, active, and capable of receiving messages before dispatching campaigns.
Read definitionDomain Age
Domain age is the length of time that an internet domain name has been registered and active, serving as a primary trust factor for ISP spam filtering algorithms.
Read definitionDomain Reputation
Domain reputation is an algorithmic score assigned to your sending domain by email service providers based on historical sending practices, engagement, and spam signals.
Read definitionEmail Deliverability
Email deliverability is the measurement of whether your emails successfully reach the recipient's primary inbox rather than bouncing or landing in the spam folder.
Read definitionEmail Hygiene
Email hygiene is the ongoing practice of cleaning, verifying, and scrubbing contact lists to remove invalid, inactive, catch-all, and honeypot email addresses.
Read definitionEmail Warmup
Email warmup is the automated process of gradually ramping up sending volume on a new email account while generating positive engagement to build high ISP trust scores.
Read definitionInbox Placement
Inbox Placement is the percentage of delivered emails that land in the recipient's primary inbox folder rather than the spam, junk, or promotional tabs.
Read definitionIP Reputation
IP reputation is a score assigned to a mail server's IP address by receiving internet service providers based on historical sending patterns and spam complaint rates.
Read definitionSpam Trap
A spam trap is an email address used by internet service providers and cybersecurity blocklist operators (like Spamhaus) to catch spammers and identify unhygienic scraping databases.
Read definitionVolume Control
Volume control is the operational discipline of capping and pacing daily email sends per inbox to protect domain reputation and prevent ISP rate-limiting.
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