Polymorphism vs Overriding vs Overloading

Question

In terms of Java, when someone asks:

what is polymorphism?

Would overloading or overriding be

Answer 1

Here's an example of polymorphism in pseudo-C#/Java:

class Animal
{
    abstract string MakeNoise ();
}

class Cat : Animal {
    string MakeNoise () {
        return "Meow";
    }
}

class Dog : Animal {
    string MakeNoise () {
        return "Bark";
    }
}

Main () {
   Animal animal = Zoo.GetAnimal ();
   Console.WriteLine (animal.MakeNoise ());
}

The Main function doesn't know the type of the animal and depends on a particular implementation's behavior of the MakeNoise() method.

Edit: Looks like Brian beat me to the punch. Funny we used the same example. But the above code should help clarify the concepts.