I've heard the term used for many years in the context of laying out on-screen user interfaces. It's specifically referring to how much screen area is being uti

I've heard the term used for many years in the context of laying out on-screen user interfaces. It's specifically referring to how much screen area is being utilized for a certain feature or area. As in "This 2-axis positioning widget is neat but it's taking up a lot of screen real-estate we could be using to surface other features."