n. The degree to which an object, device, software application, etc. is easy to use with no specific training.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. the quality of being able to provide good service
Word Usage
"We think about using transportation and we expand the term usability to include not just ease of use, but practical use, ecofriendly and economical use of transportation."