How can I stop autocorrect in a granular way? I misspell "maintenance" all the time. I usually ignore the autocorrect suggestion and just send it. Recently my iPhone (and iPad and MacBook - thanks iCloud) have started suggesting the misspelling of this word as a correction. 

It's one thing for me to ignore an error, but it's another for it to suggest the error as a correction later on. How do I change this behavior? I don't want to turn off autocorrect, I just want to remove this misspelling from the autocorrect suggestions. It also doesn't appear in "shortcuts" in keyboard settings, since it was never defined as a shortcut.
When you type something several times and ignore the suggestion, iOS assumes you mean to type it that way and adds the word to the Keyboard Dictionary. You can reset the dictionary by going to Settings > General > Reset and tapping "Reset Keyboard Dictionary". You cannot reset the dictionary in a granular way.

A possible workaround, however, if you don't want to reset the whole dictionary, is to add the misspelling as a shortcut and set the replacement phrase as the word spelled correctly. To do this go to Settings > General > Keyboard.