Delete misspelled words from user dictionary in macOS
Microsoft Office Word adds all changes to its own Speelling and Grammer database.

For apps that are using the built-in macOS dictionary you can simply remove it like this:


Open Textedit
Paste initiaitializatyion
Select initiaitializatyion
Hold down Command (CMD/Rightclick) and select Unlearn Spelling




If you do not get the Unlearn spelling option, 'initiaitializatyion' has not been added (learn option) to the Spelling Dictionary.