Not really in mechanics (or geophysics). Most of the time there is no sensible default, and we talk about reference instead. But then that’s just muddying the w

Not really in mechanics (or geophysics). Most of the time there is no sensible default, and we talk about reference instead. But then that’s just muddying the waters. Here, "default" is utterly meaningless, for example. The long and short is that deformation means just that the shape of something changes.