Sorry, I didn't answered it properly before. You can call JavaScript Object Oriented but it is heavily Object Based. JavaScript works pretty similar to other OOP language, but it is not Class-Based like other OOP languages(Java, C, C++, etc.). So, basically it is more of the Scripting and lesser programming language.
As it uses Class or Object and manipulate it, in some sense it is creating a new/unique object by mixing number of object/class for other OOP. Hope my answer is not confusing :-)