https://en.wikipedia.org/wiki/Word_processor
I think a lot of people have forgotten that “word processors” were originally mechanical devices, and then electrical and electronic devices, before ultimately becoming software.
Difference between Word Processor and text editor is in WYSIWYG mode of operation. At least for most of people.
Like my Sciter.Notes (https://notes.sciter.com) has better chances to be named as Word Processor as its primary mode is WYSIWYG. It also supports WordGrinder alike mode (Markdown editing) so users can chose what mode is more suitable for particular document type.
<graybeard> No, that's the difference between a page layout system and a word processor. </graybeard>
More seriously, word processor is to the tuple (natural language, text editor) as IDE is to the tuple (programming language, text editor). WYSIWYG is a (very, now) common feature of word processors like visual designers are a common feature of an GUI development focussed IDEs, but its not the definition of the category.
> word processor, computer program used to write and revise documents, compose the layout of the text, and preview on a computer monitor how the printed copy will appear. The last capability is known as “what you see is what you get” (WYSIWYG; pronounced wi-zē-wig).
and
> Before word processors were available, text-editing programs offered the basic editing capabilities of word processing but without WYSIWYG. WYSIWYG depends on high-resolution bit-mapped computer graphics displays.
So encyclopaedical definition of WP puts WYSIWYG as definitive characteristic of WP from TE.
Of course it's 2023, and Encyclopedia Britannica is not exactly in its best years, or the best source for canonical IT information.
Unlike Encyclopedia Britannica editors, here we have people who wrote, sold, and have used word processors without WYSIWYG in the 80s and even 90s, and they were absolutely known as word processors. In fact the first WYSIWYG offering ones, were often called "WYSIWYG word processors" to differentiate them.
Not that "and preview on a computer monitor how the printed copy will appear" is not what you think it is, in other words, it's not live "WYSIWYG" mode, MS Word-style. It also describes the mere ability to preview a rendering of the final page (as will be printed), while you do your layout in another mode. Kind of like Markdown preview today.