Full Idea
We can say that an object essentially has a certain property if its having that property follows from every definition of the object, while an object will definitively have a given property if its having that property follows from some definition of it.
Gist of Idea
An object only essentially has a property if that property follows from every definition of the object
Source
Kit Fine (Ontological Dependence [1995], III)
Book Reference
-: 'Aristotelian Society' [], p.285
A Reaction
Presumably that will be every accurate definition. This nicely allows for the fact that at least nominal definitions may not be unique, and there is even room for real definitions not to be fully determinate (thus, how far should they extend?).
Related Idea
Idea 14261 There is 'weak' dependence in one definition, and 'strong' dependence in all the definitions [Fine,K]