webhook
Pronunciation: WEB-hook
An HTTP callback mechanism that allows one application to send real-time data to another application whenever a specified event occurs, without the receiving application polling for updates.
Full Definition
A webhook is a user-defined HTTP endpoint in a receiving application that a sending application calls automatically when a trigger event fires. Unlike APIs where the client makes requests to the server on demand, webhooks reverse the flow: the server pushes notifications to the client. Common uses include notifying a CI/CD system of a new code push or alerting a Slack channel when a payment is processed. In editorial work, 'webhook' is one lowercase word. Editors should note the common confusion between webhooks and APIs: webhooks are event-driven and server-initiated, whereas API calls are on-demand and client-initiated.
Usage
Usage note: One word, lowercase. Distinguish from WebSocket (persistent two-way connection) and polling (where the client repeatedly requests updates). Plural: 'webhooks'.
In Context
- "Configure a webhook in the dashboard to receive payment confirmation events in real time." — Payment platform integration guide
- "The webhook payload is delivered as a JSON object via a POST request to the specified URL." — API reference