How to check the spelling of an entire word list

To spell check all the words/phrases in the current word list, go to the edit menu in the menu bar and select "Spell Check List" (or press 'command-;'). If there are no words/phrases misspelled, a notice will appear on the main window letting you know that there are no errors.

If the word/phrase is not spelled correctly, you will be presented with a dialog sheet (like the one pictured below) giving you your options.