At what point of decay does a zombie become a skeleton?

This question has been raised in another topic and I would like to discuss it here.

We have two opinions so far:

@Shandyr, unless maybe we imagine them as the kind of horror movie skellies who still have pieces of muscle, organ, and flesh dangling from those bones, as well as intact, horribly unlidded eyes staring from the skull sockets. Mwah,hah,hah,hah. (Flash of lightning and clap of thunder..)

@belgarathmth is calling that skeletons while I would call the following skeletons:

I imagine skeletons as they are shown as the BG sprites, very clean skeletons - whereas when you take a skeleton and put some remains of the body on it, some loose flesh and organs and stuff like that you will get a zombie.

On the other hand when a zombie gets very old and all of its organs and flesh and so on have been completly decayed and only the bones are left then it has become a skeleton.

What is your opinion on that?

We'd especially like @Mortianna's opinion on this. And @LadyRhian's.

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