How do keep auto-correct from making one particular change An email address I frequently type into web forms is srs@.... Yesterday auto-correct started changing the srs to sis as soon as I typed @. While keeping the rest of auto-correct working I would really like it to leave srs alone.

In my searching for an answer I found Is it possible (and how do I do it) to change what word Auto-Correct chooses when I make a typo? But I'm not making a typo.

I found a variety of answers for both OS X and iOS, but none seemed to the point. The worst was decrypting a substitution file maintained by Safari to edit?!
Add a text replacement for srs to srs. This appears to preempt autocomplete from changing it. The technique is the similar to this answer for how to choose the correction to a typo.

To suppress a specific auto-correction:


Open System Preferences
Open Keyboard
Choose the Text tab.
Click the + below the replacement list.
Add the same word to the Replace and With columns
Close System Preferences.