Email, CRM & retention glossary
Plain-language definitions for the systems behind customer retention
Use this glossary to align teams around lifecycle, email, CRM, automation, deliverability, experimentation, and measurement terms.
Usage note: Definitions describe practical marketing usage. Exact formulas and legal meanings can vary; document the definition used by your team.
Abandoned cart
A lifecycle journey for an identified shopper who added an item but did not complete the intended purchase. See the abandoned cart strategy.
Activation
The behavior showing a new customer or user reached an early value milestone. lifecycle automation guide.
Attribution
A rule for assigning credit to marketing touchpoints. Attribution is not automatically proof of incremental impact. retention metrics guide.
Automation
A rules-based journey triggered by customer, operational, or time-based context. automation service.
Bounce
A message that could not be delivered. Hard and soft bounces indicate different failure conditions. deliverability guide.
Campaign
A planned communication sent to an eligible audience at a chosen time, distinct from an always-on automation. email marketing service.
Churn
The end or meaningful decline of a customer relationship, defined according to the business model. retention strategy guide.
Click-through rate
The share of delivered messages that generated a tracked click; useful diagnostically but not a complete business outcome. measurement guide.
Cohort
A group sharing a starting event or period, used to compare behavior over time. retention metrics guide.
Contact policy
Rules governing permission, frequency, channel priority, suppressions, and message collisions. CRM marketing service.
Conversion
Completion of a defined action such as purchase, booking, activation, renewal, or qualified inquiry. marketing funnels.
CRM marketing
The discipline of using customer identity, history, behavior, permission, and lifecycle context to choose the next action. CRM versus email guide.
Customer lifetime value
An estimate of customer economic value across a defined relationship horizon and methodology. retention metrics guide.
Customer lifecycle
The changing stages and decisions across a customer relationship, including acquisition handoff, value, return, risk, and reactivation. lifecycle marketing.
Deliverability
The ability of legitimate email to reach a place where recipients can reasonably find it. deliverability guide.
DKIM
A cryptographic email authentication method that lets receiving systems validate an authorized signature. deliverability guide.
DMARC
A domain policy and reporting layer using SPF and DKIM alignment. deliverability guide.
Engagement segment
An audience grouped by recent channel interaction, ideally used alongside customer behavior and relationship context. segmentation guide.
Exit rule
A condition that removes someone from an automation when its job is complete or no longer appropriate. automation examples.
Frequency cap
A limit on eligible messages over a period to manage contact pressure. CRM marketing.
Holdout
An eligible comparison group intentionally not receiving a treatment, used to estimate incremental effect. measurement guide.
Incrementality
The change caused by an intervention beyond what would otherwise have happened. retention metrics.
Lead nurture
A staged journey that helps a prospective buyer progress through a considered decision. B2B nurture guide.
Lifecycle stage
A defined relationship state that changes an eligible action, message, service, or measurement treatment. CRM marketing.
List hygiene
Practices for maintaining valid, permissioned, accurately suppressed, and appropriately engaged email audiences. CRM data hygiene guide.
Open rate
The share of delivered emails recording an open event; privacy technology makes it an imperfect signal. deliverability guide.
Post-purchase
Communication after an order that can support fulfillment clarity, product success, service, and the next appropriate action. post-purchase guide.
Preference center
A customer-facing way to choose topics, frequency, channels, or other communication preferences. CRM marketing.
Reactivation
A return to meaningful activity after a defined decline or lapse. win-back guide.
Recency, frequency, monetary value (RFM)
A segmentation method grouping customers by how recently, often, and substantially they purchased. RFM guide.
Replenishment
A journey timed around a credible need to replace or reorder a consumable product. automation guide.
Retention rate
The share of a defined starting population that remains active according to a stated rule and time window. retention metrics.
Segmentation
Grouping customers by context that changes a real marketing, service, or measurement decision. segmentation guide.
Sender reputation
Signals mailbox providers may use when evaluating mail from a domain or infrastructure. deliverability guide.
SPF
An email authentication mechanism identifying systems permitted to send for a domain, subject to alignment and forwarding limitations. deliverability guide.
Suppression
A rule preventing a message or journey for reasons such as consent, recent action, service issues, fatigue, or ineligibility. CRM marketing.
Sunset policy
A documented approach for reducing or ending marketing to persistently unresponsive or inappropriate recipients. deliverability guide.
UTM parameters
URL query parameters used to label campaign traffic in analytics; they support attribution but do not prove causality. measurement guide.
Welcome flow
An automated journey that confirms expectations, introduces value, supports the first action, and adapts after conversion. welcome flow guide.
Win-back
A structured attempt to re-engage a customer whose normal relationship has meaningfully declined. win-back guide.
Zero-party data
Information a person intentionally provides, such as a preference, goal, or declared need. segmentation guide.