Vertical space refers to the physical or virtual distance between objects or elements that are arranged one above the other. It describes the amount of empty or filled space in a vertical direction. Full definition
Most kitties really enjoy being up high, and many cat parents do not make good use of vertical space in their homes. (cat-lovers-only.com)
Make sure that every inch of vertical space in your kitchen is treated with the respect it deserves and make sure that you view the entire space as one entity. (thesinglenester.com)
This space does a particularly great job using vertical space by pairing the arc lamp with tall shelving. (eurostylelighting.com)