iirish software package provides Irish (Gaeilge) dictionary for ispell, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install iirish
iirish is installed in your system.
Make ensure the iirish package were installed using the commands given below,
$ sudo dpkg-query -l | grep iirish *
You will get with iirish package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Text Processing |
| Package | iirish |
| Version | 2.0-24 |
| Description | Irish (Gaeilge) dictionary for ispell |
| Sub Section | Text |