Hmm, I meant stable compound in the sense of a noble gas, not highly volatile or reactive. Or say, lower energy states that are not as likely to emit a photon.

The horse is "unstable'd", maybe another way of saying it. Unstable is developed outside of the stable release engineering process. That does not mean it's without safeguards. The unstable releases tend to be very stable. There are extra safeguards, and time-based safety measures that protect users of the Stable distribution. They say that Unstable might take longer to get fixes, and while that's likely true in the case of critical fixes with special attention, it's almost never true in practice other than that. Unstable receives fixes much more quickly, in general.

There actually used to be a "debian-volatile" project, too, for things like virus definitions that should be used in a stable distribution, and also didn't make sense to govern through the stable release process, but it is defunct now.