You can add terms to both local and remote glossaries. To add terms to a remote glossary, you need read and write user permissions. You cannot add terms to a read-only glossary.
To add a term to a glossary:
In the Terminology pane, select a word in the source segment and, optionally, the translation in the target segment, then click .
In the resulting Add Term dialog, enter content in the Description field.
Select the proper Glossary from the drop-down list.