Cold email & deliverability glossary
162 plain-language definitions for cold outreach and deliverability.
Metrics
Deliverability
DNS & infrastructure
- SPF
- DKIM
- DMARC
- BIMI
- MX record
- TXT record
- CNAME record
- PTR record
- A record
- NS record
- DKIM selector
- SPF include
- SPF lookup limit
- DMARC policy
- DMARC rua
- Custom tracking domain
- Return-path
- From domain
- HELO / EHLO
- MTA
- Mailbox provider
- Google Workspace
- Microsoft 365
- Proofpoint
- Mimecast
- Punycode
- TTL
- Nameserver propagation
- DMARC quarantine
- DMARC reject
- ARC
- BIMI VMC
- WHOIS privacy
- Registrar
- DNS host
Finding & verification
- SMTP
- Catch-all domain
- Accept-all
- Email verification
- Syntax check
- MX check
- Mailbox check
- SMTP verification
- Role address
- Disposable email
- Free email provider
- Email finder
- Email pattern
- Email permutator
- False positive
- False negative
- Confidence score
- Domain pattern
- Catch-all confidence
- Not found
- Predicted
- Verified email
- Work email
- Personal email
- Alias
- Plus addressing
- Subaddressing
- Internationalized email
Data & enrichment
Outbound & cold email
- Cold email
- Cold outreach
- Outbound
- Sequence
- Cadence
- Sequencer
- Personalization
- Spintax
- Icebreaker
- Follow-up
- Breakup email
- Sending volume
- Mailbox rotation
- Primary domain
- Secondary domain
- Lookalike domain
- Unqualified
- Bulk email
- Transactional email
- Marketing email
- Double opt-in
- Split test
- Subject line
- Preview text
- Plain-text email
- Tracking pixel
- UTM parameters
Compliance
Look up a domain while you are here
Most glossary visits are a person stuck on a DNS record. Check SPF, DKIM and DMARC on the domain in question.
Related
- Free email finder, verifier, and DNS tools
Free work email finder and verifier, plus MX lookup, SPF/DKIM/DMARC checker, permutator, generators, and calculators. DNS tools are uncapped.
- Guides on verifying work emails
How to verify an email address, what catch-all domains are, SPF/DKIM/DMARC, and sourced comparisons of email finders.
- Bounce rate — cold email glossary
The share of sent emails a mail server refuses to deliver. A hard bounce means the mailbox does not exist; a soft bounce means it is temporarily unreachable.
- Hard bounce — cold email glossary
A permanent delivery failure: the mailbox does not exist, the domain does not accept mail, or the server has rejected the recipient for good. Hard bounces are the ones that wreck sender reputation.