Avyākṛta in sanskrit.
The Buddha remained silent when asked these fourteen questions. He described them as a net and refused to be drawn into such a net of theories, speculations, and dogmas. He said that it was because he was free of bondage to all theories and dogmas that he had attained liberation. Such speculations, he said, are attended by fever, unease, bewilderment, and suffering, and it is by freeing oneself of them that one achieves liberation.
This is the standard Pali or Theravada interpretation of these questions: just don't ask.
But it strikes me that a non substantial silence in response to questions is a bit of a cop out.
The easiest response is to say that the silence in response to these questions is an expression of the right way of asking them, i.e. not asking. But it simply seems wrong to say that there's way to ask what happens at his death given that the Buddha is not annihilated.
Unless we accept a form of pragmatism it seems that the actual answer to these questions is silence. That the limit of the world / space / the self / the buddha, is in some aspects only representable by the quiet mind.
So are the unanswered questions, actually answered?