Issues with `cd` after `alias`

Question

I read this command somewhere on Twitter and executed it in my Terminal and it seems it removed the cd package completely from the OS.

alias cd="say -v cello"

1. What does this command do? Can you breakup the explanation of this command?

2. How do I install cd back to Ubuntu?

Answer 1

1. That command aliases say -v cello to cd, which means now cd is a shortcut for say -v cello
2. cd cannot be installed/uninstalled separately, it's part of the shell, not a separate program. Your problem is that you're shadowing the original cd with your alias cd. If you remove that alias (unalias), it should be back.