Creating specific taxonomy terms the Drush way
Try the taxonomy manager module. 

https://www.drupal.org/project/taxonomy_manager

It allows for mass insertion of terms.

There's also a taxonomy csv module which allows for import/export of taxonomies to file. That might be worth a try too:
https://www.drupal.org/project/taxonomy_csv

Else you can try and write your own module... But that's a rather tougher route.