The definition below corresponds to how I have learnt to use the term “encapsulation”:
[quote]"In general, encapsulation is one of the four fundamentals of OOP (object-oriented programming). Encapsulation refers to the bundling of data with the methods that operate on that data.[7] Encapsulation is used to hide the values or state of a structured data object inside a class, preventing unauthorized parties’ direct access to them. Publicly accessible methods are generally provided in the class (so-called getters and setters) to access the values, and other client classes call these methods to retrieve and modify the values within the object.
This mechanism is not unique to object-oriented programming. Implementations of abstract data types, e.g. modules, offer a similar form of encapsulation. This similarity stems from the fact that both notions rely on the same mathematical fundament of an existential type.[8]"[/quote]
http://en.wikipedia.org/wiki/Encapsulation_(object-oriented_programming)