cewl software package provides custom word list generator, 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 cewl
cewl is installed in your system.
Make ensure the cewl package were installed using the commands given below,
$ sudo dpkg-query -l | grep cewl *
You will get with cewl package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Web Software |
| Package | cewl |
| Version | 5.2-1 |
| Description | custom word list generator |
| Sub Section | Web |