MS Word 2019 has suddenly slowed waaaay down

[KDuncan]

MS Word was working fine last night. This morning, it is going incredibly slow. I clicked the X to close the search dialog. That took about a minute to close. I've tried clicking on words in the text and it is not really working. I can't imagine what changed. I used Malwarebytes to look for viruses and it didn't find any. Any suggestions of what to try? I'm working against a deadline and I can't have this for a 70-page document. I've closed all my browsers. Speed in other apps, including Firefox, is fine. It is only Word that has a problem. Thanks.