This is not specifically a TeX question, but I think it might be relevant here since all TeX users are also text editor users.
I use the Emacs Aquamacs (v 3.0a) text editor. My locale on my Mac is Australian. As far as I understand Emacs applies in checking the spelling the current locale of the system is running on. I want to edit a document to be sent in the US and I then would like to change the dictionary from Australian (or British) to American English but just for one document.
I tried to navigate the Aquamacs documentation but without much success. It seems that the default
Flyspell dictionary in my Aquamacs preferences is
Standard. I couldn't find any indication to the actual dictionary file Aquamacs is using and how to change it.
EDIT: In my
~/Library/Spelling I have these dictionaries:
LocalDictionary. I can select any of these dictionaries through
Edit -> Spelling -> Change dictionary... but without any effect in the words identified as wrong by the editor. I still get all US spellings checked as wrong (e.g. "organization", "behavior") but even selecting
en as dictionary all Italian and Spanish words are not checked as wrong (e.g.
popolazione). It seems it is checking against all three dictionaries: british english, italian and spenish but not american english...