A family of Microsoft word processing software products for creating web, email, and print documents.
I have been experiencing this same issue for more than 6 months. I am running Win10 64 bit and Office 365 (2016) 64 bit version 1701 (build 7766.2099) . At certain times, with just a single Word document open, the Microsoft Word process consumes 35% - 50% of the CPU all by itself. I'm not typing, altering the document, doing anything. This is on a current generation ThinkPad with multi core i7 processor, 8Gb RAM and a SDD
I've tried all the de-installing, re-installing, changing settings, changing various drivers etc etc recommendations via all the various newsgroups and still it persists. Trying to type within Word, select items, use the ribbon etc results in at least a 1-2 second delay between every single action. I can type up to 3 words ahead and watch as the text slowly appears, letter by letter, on the screen.
It seems to be related to certain larger documents (3-5Mb each), as it only happens when I have them open. If I start with a new document and start filling it with content from scratch, Word behaves normally. It's as if there is something in those larger document that Word feels compelled to index, search, fix or identify in the background. I've turned off all the Word auto-checking tools etc to try isolate the issue, but still no joy.
It really is like going back in time a few decades to using Word Perfect on DOS... Word really becomes that slow.