If a terminology database entry was changed before, the History button is available in the header of the Entry Section, while viewing the entry. Clicking on this button will display the history of changes in the entry.
The current entry is listed first followed by its previous versions. Each version of the entry is listed as a separate Entry Section. The headers of the old versions are grey, indicating their History status, and also show their version.
Each Entry Section contains a list of attributes and their values for each version of the entry, so you can see any changes over time.