Multilingual greeter object
This is not JSON. However JSON was inspired from Javascript Native way of creating object. This is why they're really similar.

However JSON handles only data, not functions.

Furthermore you can rewrite your function like this : 

function newObj(name){
    this.name = name;
    return this;
};
newObj.prototype.greeter = function(lang){
    switch (lang){
            case "en":return "hi "+this.name;
            case "es":return "hola "+this.name;
            default: return "hello "+this.name;
    }
}

var obj = new newObj("name");
obj.greeter("de");


As you can see 


I got rid of the 2nd parameter in the newObj function since it was not used.
I bind greeter to the Object so now I can use this.name in greeter to greet you by your name.
If you try to JSONify this, everything under prototype will be ignored so you won't have any error.