Option + Z keystroke does not insert the ohm symbol/omega (Ω) Every article that I can find on web suggests the keystroke Option + z to insert that Ω symbol on a Mac. However, on my Mac, when I press that combination, I get the ˀ character. I followed the instructions in this article.
After changing my Input Source to U.S. (via System Preferences -> Keyboard -> Input Sources), the keystroke works as expected. Now pressing Option + z inserts the Ω character.