---
title: "Email Verification Glossary | Refresh List"
description: "Plain-language definitions of verification, catch-all, unknown, SPF, DKIM, DMARC, and email list hygiene."
url: https://refreshlist.net/glossary
last_updated: 2026-09-25
---

# Email Verification Glossary

Understand the evidence behind an email result and the terms used in your next campaign.

## Email List Cleaning

Preparing contact data by identifying duplicates, malformed values, and records that need review before a campaign.

## Email Verification

Checking available address and mail-server evidence to classify an email address. Verification does not establish consent or guarantee inbox placement.

## Valid

The check found evidence consistent with acceptance at the time of verification. Sender reputation, content, and later mailbox changes can still affect delivery.

## Invalid

The available evidence indicates an address should not be used as supplied. Review the detailed reason, such as syntax or a nonexistent mailbox.

## Unknown

The check could not reach a conclusive mailbox result. Keep it separate from invalid addresses and review the reported reason.

## Catch-All

A domain accepts checks for many or all recipient names. Domain acceptance alone does not establish that an individual mailbox exists.

## Role Address

An address associated with a function or team, such as sales or support. It may be deliverable but requires a campaign-specific decision.

## Disposable Address

An address associated with a temporary-email service when supported by the available classification data. A missing flag is not proof of permanence.

## Suppression

Excluding addresses that should not be contacted, such as unsubscribed recipients or previously bounced addresses. Verification does not override suppression.

## MX Record

A DNS record identifying mail servers for a domain. It describes mail routing, not the existence of an individual inbox.

## SPF

A DNS policy describing which servers are authorized to send mail for a domain.

## DKIM

A cryptographic message signature that lets receiving systems check a signing domain and whether signed content changed.

## DMARC

A policy connecting the visible From domain to SPF or DKIM alignment and describing handling and reporting preferences.

## Blocklist

A list operator’s record of IP addresses or domains associated with its listing criteria. An unavailable lookup is not a clear result.

## Deliverability

Whether messages reach their intended recipients, influenced by reputation, authentication, permission, content, and recipient policies as well as address quality.

[Read The Detailed Result Status Guide](/result-status-guide)  or [Explore The Verification Methodology](/verification-methodology) .

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