---
title: "Entity definition"
slug: "entity-definition"
abstract: "Overview of entity definition."
---
# Entity definition

An entity definition is a part of the schema that defines how a type of entity is [structured](https://doc.sitecore.com/ch/en/users/content-hub/view-entity-definition-details.html "View entity definition details"). The definition includes both descriptive properties, such as taxonomies and option lists, and relations with other entities. Collectively, properties and relations are known as entity members.

You can [create](https://doc.sitecore.com/ch/en/users/content-hub/create-an-entity-definition.html "Create an entity definition") and [edit](https://doc.sitecore.com/ch/en/users/content-hub/edit-an-entity-definition.html "Edit an entity definition") entity definitions, and define their [members](https://doc.sitecore.com/ch/en/users/content-hub/members.html "Members").

> [!important]
> For performance reasons, we recommend that the number of relation definitions assigned to any single entity definition be kept below 50.