Newsletter glossary
The terms, defined like a practitioner would.
What audience teams, editorial teams, and revenue teams actually mean when they use the words. Built from inside the workflow, not pulled from a textbook.
Glossary
Newsletter terms, defined.
Open rate
Percentage of delivered emails opened. Useful as a directional signal; less useful since Apple Mail Privacy Protection started auto-loading images. Pair with click rate and reading time.
Click-through rate (CTR)
Clicks divided by delivered. The honest engagement metric, post-MPP. Worth segmenting by content type — recommendations click differently than headlines.
Sender reputation
How mailbox providers grade your domain and IP. Built from engagement, complaint rate, bounce rate, and authentication. Drifts slowly until something breaks; then drops fast.
List hygiene
Removing addresses that hurt your reputation. Hard bounces, long-term unengaged, role accounts, traps. A weekly workflow, not a quarterly project.
Direct-sold sponsorship
Inventory you sell yourself to a specific brand for a fixed run. Higher CPM than programmatic; takes more sales work. The bread and butter for most editorial newsletters.
Programmatic ad fill
Inventory filled automatically through ad networks (GAM, LiveIntent, RevContent). Lower CPM, higher fill, no sales overhead. Best as the backstop on slots that don't sell direct.
House promotion
Cross-promotion of your own products — other newsletters, paid tiers, events, products. The most efficient inventory you have if you actually use it.
Engagement segment
A subscriber group built from interaction patterns, not declared attributes. The audience that opens every send is a different audience than the one that opened twice last quarter.
Pre-flight
Automated checks that run before send: brand guidelines, broken links, spam-score, clipping risk, render quality across providers. Catches the things QA misses at midnight.
Clipping
When Gmail truncates an email over ~102KB and adds a "View full message" link. The bottom of your newsletter — including unsubscribe and ad slots — disappears. Avoidable with slim HTML.
Authentication (SPF / DKIM / DMARC)
The three records that tell mailbox providers your sends are legit. Breaking one silently is the most common cause of an overnight engagement drop.
Newsletter portfolio
A set of related newsletters run by one team or company. The unit of analysis for audience teams who care about cross-newsletter behavior, overlap, and growth.
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