"Useable space" refers to the area or room that can be fully utilized or put to practical use. It describes a place or an area where you can perform activities, store things, or carry out tasks effectively. Full definition
The front - wheel drive design was a must, if the 2 Series Active Tourer were to have even a modicum of useable space in the rear. (autofocus.ca)
And the trunk design focuses on useable space, taking into consideration everything from the size of the hinges to the shape of the sidewalls. (thetorquereport.com)
The Kia Soul has less power, but then it weighs less as well, with comparable fuel economy but much more useable space. (cnet.com)