As with pages, general glossaries can also be translated. When creating a taxonomy term, however, it is better that you create it from the source language of the website. 

You can easily change this when you create the term, next steps show how to create the taxonomy:

  1. Go to the structure > Glossaries > and choose the desired glossary. 
  2. Add a word to the glossary.
  3. Choose the original language of your website

  1. Create your term. 
  2. When you have created your term, click on the arrow under Actions for your new term.
  3. Select Translate
  4. Translate your term into the appropriate language.