Comment by cyphunk

I disagree with this interpretation. It remains 0 day until it is patched or has a work around (disabling the service). Further still the date aging starts begins when the bug is disclosed publicly, or broadly if not publicly. Internal disclosure doesn't count. It remains 0day even if you share it with a friend. The measurement of days has to do with its usefulness (to an attacker) and that begins to diminish after wide disclosure. Then again, the term is also completely irrelevant.