Frequently misspelled words are listed alphabetically throughout this style manual. Also listed are preferred spellings for words with more than one possible spelling. Based in the United States, this manual prefers American spellings to British spellings, except for names of British publications and organizations.
For spelling and definitions not covered in this manual, check a dictionary. If two (or more) spellings are listed, use the first one unless this manual lists a specific exception. If your dictionary provides different spellings in separate entries (gray and grey, for example) use the spelling followed by a full definition (gray). If a dictionary entry is listed as usually or often, use that entry.
Use computerized spelling checkers carefully; they don't catch mistyped words that are spelled correctly - not instead of now--or words that sound alike but are spelled differently - too, two, to.