iOS 11.1.1 is out to squash the bug.

 

Apple released an update to iOS 11 today to fix the autocorrect bug that has been confusing and/or annoying the internet.  Head on over to Settings > General > Software Update to install iOS 11.1.1.

As always, I recommend ensuring you have a backup prior to installing any update. The full rundown of the update is available from Apple Support.