Semantic equivalence
# Semantic equivalence

In computer metadata, semantic equivalence is a declaration that two data elements from different vocabularies contain data that has similar meaning. There are three types of semantic equivalence statements:

* Class or concept equivalence. A statement that two high level concepts have similar or equivalent meaning.
* Property or attribute equivalence. A statement that two properties, descriptors or attributes of classes have similar meaning.
* Instance equivalence. A statement that two instances of data are the same or refer to the same instance.

## Example

Assume that there are two organizations, each having a separate data dictionary. The first organization has a data element entry:

and a second organization has a data dictionary with a data element with the following entry:

these two data elements can be considered to have the same meaning and can be marked as semantically equivalent.

