Space in which an object is defined.

We can talk about the domain of a study, the domain of a science, the domain of a statistical inquiry, the domain of a numerical relationship, and so on. The domain sets the range and the limits of a concept or an intention. The meanings used in mathematics reflect this broad definition.

The **domain of a relation** is the set of the origins of the pairs of this relation.

### Example

In the relation of E toward F illustrated here, the domain is {2, 4}.

In fact, we have {2, 4} ⊆ {2, 3, 4, 5}.

### See also :

- Domain of definition of a variable
- Domain of a function
- Set of departure of a function.