If you are going to use nvm installations with gnome-terminal, you'll probably need to change it's default options.

Multi-User nvm creates a script in /etc/profile.d, which is being sourced on startup. Also, most people put the nvm sourcing line required to load nvm in their ~/.bash_profile for Single-User installs. By default, gnome-terminal runs Bash as usual, as a non-login shell, therefore skipping /etc/profile* and executing only the user's ~/.bashrc. This means that nvm doesn't load and you get the infamous 'nvm is not a function' message.

For nvm to work properly, you have to set the 'Run command as login shell' checkbox on the Title and Command tab inside of gnome-terminal's Settings page.

*Proudly taken from https://rvm.io/integration/gnome-terminal