How Do I Edit Or Remove Words From The User Dictionary In OS X Lion?
Your Library folder is hidden in OS X Lion. Before we can edit the Dictionary, the Library folder has to be made visible. To do that, open the Terminal app and type (without quotes) "chflags nohidden ~/Library/" and push return. Your Library folder should now be visible. You can also open the Library folder by going to the Go menu in the Finder and holding down the option key. The Library folder will appear in the menu.
To access the Library folder, open your hard drive and navigate to Users/yourname/Library/Spelling. There should be a file called LocalDictionary. Open that file in TextEdit, remove the misspelled word, and save your changes.