deluser

Remove a user

$ sudo deluser [username]

$ sudo deluser --remove-home [username]

$ sudo deluser --backup-to [path/to/backup_directory] --remove-home [username]

$ sudo deluser --remove-all-files [username]

$ sudo deluser [username] [group]

deluser [options] user [group]

deluser removes users from the system. It can optionally remove the user's home directory, mail spool, and other files. It's the Debian/Ubuntu counterpart to userdel.
When given both a user and group name, it removes the user from that group without deleting the user account.

--remove-home

Remove user's home directory

Remove all files owned by user

Backup files before removal

Backup destination directory

Only delete if system user

Requires root privileges. Use --backup when removing important users. The user must not be logged in. On non-Debian systems, use userdel instead.

userdel(8), adduser(8), delgroup(8)