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.
