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Email Verification & Deliverability
Email Verification & Deliverability Glossary
Published: 12/4/2025
A complete guide to the essential terms every marketer and sender should know. Email deliverability is complex. From spam traps to exhaustion, risk scoring, and behavioral signals, understanding the terminology is the first step toward safe, high-performing campaigns. This glossary provides clear, practical definitions of the most important terms in email verification, hygiene, and deliverability. Active / Inactive Emails
Bounce / Bounce Codes
Bounce codes explain the reason for delivery failure. Campaign Warm-UpThe process of gradually sending emails from a new or dormant IP/domain to build trust and reputation with mailbox providers. Data IntegrityEnsuring all email addresses in your list are accurate, active, and safe to send to. High data integrity protects reputation, inbox placement, and revenue. Decayed / Exhausted Emails
Sending to decayed or exhausted emails reduces engagement and increases risk. Disposable / Temporary EmailsEmails created for one-time or short-term use. They often bypass verification but pose high risk for reputation and deliverability. Engagement MetricsIndicators of recipient interaction:
High engagement signals improve sender reputation; low engagement increases risk. High-Risk EmailsEmails likely to harm campaigns due to:
High-risk emails are scored and suppressed by predictive hygiene platforms like Impressionwise. Predictive HygieneAdvanced list hygiene that predicts risk before sending, combining:
It goes beyond verification to protect reputation and inbox placement. Risk ScoringA numeric or predictive score assigned to email addresses based on likelihood to harm deliverability or engagement. Factors include: behavior, source, traps, exhaustion, and domain integrity. Spam TrapsEmail addresses created specifically to catch negligent senders. Triggering a spam trap can instantly damage sender reputation. Verification vs Validation vs Risk
Sender ReputationA score mailbox providers assign based on sending behavior, engagement, bounces, complaints, and traps. Strong reputation = inbox placement; while weak reputation = spam foldering. Source IntegrityEvaluating the origin of your email addresses to ensure they are safe, engaged, and high-quality. Weak sources increase risk of traps, exhaustion, and spam complaints. Warm-Up SchedulesA structured plan for gradually increasing email volume from a new or dormant IP/domain to build trust and maintain reputation. Safe warm-up avoids throttling, spam filtering, and engagement loss. Final NoteMastering these terms is the foundation for successful, safe, and high-performing email campaigns. Impressionwise applies all of these concepts in a predictive hygiene framework, protecting lists, engagement, and deliverability from hidden risks. |
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