How to set the autocorrection and dictionary to the same language in Mac OS X Mavericks How can I change the system to stop making corrections like so:



Please notice that the two words on the left have the dotted red line indicating that they are spelled in the wrong way.

Then, if I click the option "Look up" on the contextual menu on the right, the dictionary says the word is like on the left, where it is marked with the red line indicating the wrong spelled word.

I would like to set my system to use the same dictionary on the "look up" option and auto correction options.

I also found this post that may be the solution to the problem, but it seems it only applies to Lion.
Assuming you are running OS X Mavericks you have to open System Preferences, click Keyboard, then click Text, if you are looking for the settings shown in the link you provided. On the right there is a drop down menu, that let you configure the language priority like mentioned in blog post.