sustainable thesaurus. Retrieved October 19, 2015, from http://www.powerthesaurus.org/sustainable/synonyms.
the mass of the object determines the amount of inertia in an object. Mass determines the amount of inertia an object has. It is an object's intrinsic property to resist change. the two main things are speed and velocity. You have to factor in a bunch of smaller things too, but those don't really have much effect.
In common usage, the term inertia may refer to an object's amount of resistance to change in velocity (which is quantified by its mass), or sometimes to its momentum, depending on the context.