gnome-dictionary software package provides GNOME dictionary application, 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 gnome-dictionary
gnome-dictionary is installed in your system.
Make ensure the gnome-dictionary package were installed using the commands given below,
$ sudo dpkg-query -l | grep gnome-dictionary *
You will get with gnome-dictionary package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | GNOME |
| Package | gnome-dictionary |
| Version | 3.20.0-3 |
| Description | GNOME dictionary application |
| Sub Section | gnome |