I am writing a text with a lot of foreign words, and MS Word complained that there were too many ‘errors’ and stopped checking spelling. Is there a way to force spellchecking? (Short of creating a separate style, which I do for entire sentences but which would be impractical for isolated words.) I have foreign words in italics; letting Word know that italics are off-limit would work.
You need to install a foreign dictionary
Microsoft Word can use multiple custom dictionaries to check the spelling of your documents. A custom dictionary allows you to supplement the main dictionary with additional words, such as names, specialized technical terms, foreign words or alternative spelling of some words.
Or find them online.
But many languages are built in and you just have to choose them from an internal menu.