In plain language
It uses a stable identifier or defined matching rule to avoid repeated contacts, orders, messages, or workflow effects.
Example
Before creating a contact, a workflow searches for an existing record with the same normalized email address.
Related terms
Idempotency · Trigger · CRM
Common misconception
Deduplication is not the same as deleting anything that looks similar; weak matching can incorrectly merge different people or events.
Implementation guidance
Choose a durable unique key, normalize inputs, use atomic upserts where possible, and send uncertain matches to review.