# Are Newton's "laws" of motion laws or definitions of force and mass?

If you consider [them](http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion) as laws, then there must be independent definitions of [force](http://en.wikipedia.org/wiki/Force) and [mass](http://en.wikipedia.org/wiki/Mass) but I don't think there's such definitions. If you consider them as definitions, then why are they still called laws?