Can I disable auto-correction of a single word on OS X? I'm running into an annoying issue with OS X's automatic spelling correction where the word nala gets automatically corrected to napa.

I've tried adding nala to my custom dictionary under ~/Library/Spelling/LocalDictionary but it still reliably makes the correction anyway.

How do I configure OS X to not automatically correct a given word short of turning off automatic correction entirely which is not really desirable?
Yes you can do it.  


Go to System Preferences > Keyboard > Text.  
Click the + sign on the bottom left to add a new text replacement.
In the Replace column, put the word you want OS X to stop autocorrecting (no spaces are allowed).
In the With column, put the exact same word you put in the Replace column.


Voila.  You're done.

This has worked flawlessly for me every time.