Word 2016 Mac set default window size

[FnuLnu]

Cannot figure out how to open docs in a custom window size, as opposed to opening at full screen. I have set defaults for font, doc format, zoom to where I want them. What I cannot find is how to set the window size so that each new doc opened, opens at approx half the screen size (a custom size I want). Right now every new doc opens with my correctly set "zoom to whole page" size, within a window that takes up the entire screen. Each time I have to drag the window size to just larger than the whole page sized doc. Thanks for any help.