Glossary/Email & Lifecycle

• 10-Digit Long Code (10DLC)

  A standard 10-digit U.S. phone number registered with carriers for business application-to-person texting at moderate volumes.

• Brand Indicators for Message Identification (BIMI)

  An email standard that displays a brand's verified logo next to messages in supporting inboxes, requiring DMARC enforcement first.

• Browse Abandonment Email

  An automated email sent to a known visitor who viewed products without adding to cart, reminding them of the items they browsed.

• Bulk Sender Requirements

  Gmail and Yahoo rules since 2024 requiring high-volume senders to authenticate, offer one-click unsubscribe and keep spam rates below 0.3%.

• Click-to-Open Rate (CTOR)

  Unique clicks divided by unique opens, showing how compelling an email's content was to those who opened it.

• Customer Health Score

  A composite score in a CRM or customer success tool that predicts a customer's likelihood to renew, expand, or churn based on usage and engagement.

• Deal Stage

  A step in a CRM sales pipeline, such as discovery, proposal, or negotiation, that tracks an opportunity's progress toward closing.

• Dedicated IP

  A sending IP address used by only one sender, so its reputation depends entirely on that sender's own email practices.

• DMARC

  A DNS policy built on SPF and DKIM telling receivers how to handle failing emails (none, quarantine or reject) and sending reports.

• DomainKeys Identified Mail (DKIM)

  An email authentication method that adds a cryptographic signature proving a message wasn't altered and came from the claimed domain.

• Double Opt-In

  A signup process requiring subscribers to confirm their address via a confirmation email before being added to a list.

• Drip Campaign

  A series of automated emails sent on a set schedule or in response to actions, nurturing contacts over time.

• Dynamic Email Content

  Sections of an email that change automatically for each recipient based on data such as location, behavior, or segment.

• Email Blocklist (DNSBL)

  A public list of IP addresses or domains flagged for sending spam, which mailbox providers consult to block or filter incoming email.

• Email Conversion Rate

  The percentage of email recipients or clickers who complete a desired action, such as a purchase or sign-up, after engaging with an email.

• Email Deliverability

  The ability of emails to reach the inbox rather than spam or being blocked, driven by authentication, reputation and engagement.

• Email Service Provider (ESP)

  A platform used to build, send, and track marketing or transactional email at scale, such as Mailchimp, Klaviyo, or SendGrid.

• Email Verification

  Checking email addresses for validity, typos, disposable domains, or risk before sending, to reduce bounces and spam trap hits.

• Feedback Loop (FBL)

  A service from mailbox providers that notifies senders when recipients mark their email as spam, so those addresses can be suppressed.

• Google Postmaster Tools

  A free Google dashboard showing bulk senders their Gmail spam rate, domain and IP reputation, and authentication results.

• Graymail

  Bulk email a recipient opted into but rarely engages with, which mailbox providers may increasingly filter away from the inbox.

• Hard Bounce

  A permanent email delivery failure, such as an invalid or nonexistent address, that should be removed from the list immediately.

• Inbox Placement Rate

  The percentage of delivered emails that land in recipients' primary inbox rather than the spam or junk folder.

• IP Warming

  Gradually increasing email volume from a new sending IP address so mailbox providers can build trust and avoid filtering it as spam.

• Journey Orchestration

  Coordinating personalized, real-time messages across email, SMS, push, and other channels based on each customer's behavior and lifecycle stage.

• Lead Nurturing

  Building relationships with prospects not yet ready to buy through relevant, staged content until they become sales-ready.

• Lifecycle Stage

  A CRM field marking where a contact sits in their relationship with a company, such as subscriber, lead, MQL, SQL, opportunity, or customer.

• List Growth Rate

  The rate at which an email or SMS list grows over a period, calculated as new subscribers minus unsubscribes, bounces, and complaints, divided by list size.

• List Hygiene

  Regularly cleaning an email list by removing invalid, bouncing and unengaged addresses.

• List-Unsubscribe Header

  A hidden email header that lets mailbox providers show a built-in unsubscribe button, giving recipients an alternative to marking mail as spam.

• Mailbox Provider (MBP)

  A company that hosts email inboxes and decides inbox placement, such as Gmail, Outlook, Yahoo, or Apple iCloud Mail.

• One-Click Unsubscribe

  A standard (RFC 8058) letting recipients unsubscribe in a single click from the inbox interface, now required by Gmail and Yahoo for bulk senders.

• Open Rate

  The percentage of delivered emails that were opened, now less reliable because privacy features inflate tracked opens.

• Post-Purchase Flow

  An automated series of emails after a purchase, such as order confirmation, onboarding tips, review requests, and cross-sell offers.

• Preference Center

  A page where subscribers choose which topics, channels, and frequency of messages they receive, reducing full unsubscribes.

• Preheader Text (Preview Text)

  The short summary text shown after the subject line in most inbox views, used to boost open rates.

• Re-Permission Campaign

  An email asking inactive or older subscribers to confirm they still want to receive messages, removing those who do not respond.

• Revenue Per Recipient (RPR)

  Total revenue attributed to an email campaign or flow divided by the number of recipients, a common ecommerce email performance metric.

• Rich Communication Services (RCS)

  An upgraded mobile messaging standard that adds branding, images, carousels, and buttons to texts, supported on Android and on iPhones since iOS 18.

• Seed List

  A set of test inboxes across mailbox providers that a sender emails to check whether messages land in the inbox, spam, or other tabs.

• Segmentation

  Dividing an audience into groups by shared traits or behaviors so messages can be tailored to each.

• Send-Time Optimization (STO)

  Using each recipient's past engagement data to deliver email at the time they are most likely to open it.

• Sender Policy Framework (SPF)

  A DNS record listing which mail servers may send email for a domain, helping receivers detect spoofing.

• Sender Reputation

  A score mailbox providers assign a sending domain and IP based on complaints, bounces and engagement, affecting inbox placement.

• Short Code

  A five- or six-digit phone number used for high-volume, pre-approved SMS marketing in the U.S. and Canada.

• Single Opt-In

  A subscription method where a contact is added to a list immediately after signing up, without confirming via a follow-up email.

• SMS Keyword

  A word customers text to a number, like JOIN or STOP, that triggers opt-in, opt-out, or an automated reply.

• Soft Bounce

  A temporary email delivery failure, such as a full mailbox or server issue, that may succeed if retried later.

• Spam Complaint Rate

  The share of recipients who mark an email as spam; mailbox providers expect it well below 0.3%.

• Spam Trap

  An email address used by mailbox providers or blocklist operators to catch senders with poor list practices; mailing one damages sender reputation.

• Subject Line Testing

  Sending different subject line versions to subsets of a list to see which earns more opens or clicks before sending the winner.

• Sunset Policy

  A rule that stops emailing subscribers after a set period of no engagement, protecting deliverability by removing inactive contacts.

• Suppression List

  A list of addresses that must never be emailed, such as unsubscribes, hard bounces, and spam complainers, applied automatically to every send.

• Transactional Email

  An automated email triggered by a user action that delivers necessary information, such as a receipt, password reset, or shipping notice.

• Triggered Email

  An automated email sent in response to a specific behavior or event, like a signup, purchase or inactivity.

• Unsubscribe Rate

  The percentage of delivered emails that result in a recipient opting out, a key signal of content relevance and send frequency.

• Verified Mark Certificate (VMC)

  A digital certificate proving a brand owns its trademarked logo, required by Gmail and others to show that logo via BIMI.

• Web Push Notification

  A clickable alert sent through a browser to opted-in website visitors, even when they are not on the site.

• Welcome Series

  Automated emails sent right after someone subscribes or signs up, introducing the brand and guiding first actions.

• Win-Back Campaign

  Messaging aimed at lapsed customers or inactive subscribers to bring them back, often with an incentive.