A lot of people have been speculating, wondering, or asking what the name “Numenera” means. The answer is complex. To start with, “Numen” is one of my favorite somewhat obscure words. I also like the closely-related “numinous.” It has many different meanings, and all of them play into the game really well. Numen means “an influence perceptible by mind but not by senses.” More specifically, it relates to “the presence of the divine.” More generally, it relates to anything supernatural.
Numen, a Latin word, also means potential. In some more modern belief systems, Numen refers to a spirit or magical essence within an object. What a great way for someone to look at technology so advanced that it is indistinguishable from magic, as Arthur C. Clarke said.
If we really stretch (and sticklers won’t like me stretching this far), there is also a linguistic connection with “nine,” so it’s not hard to pretend that it refers to “Ninth Era,” or “Ninth World,” which is the name of the setting.
Era, of course, is a long period of time. Usually of fairly arbitrary length, even when it is a specific period (as in “Mesozoic Era”).
So “Numenera” could be thought to mean, “the age of the divine,” which isn’t such a terrible way to describe how humanity in the Ninth World setting would look upon the past. It could also be “the age of potential,” which would be a way to describe the Ninth World itself–a new age of humanity, full of potential. A new beginning.
Era is also close to aera or aero, which of course refers to the air. Numen aera, in Latin, might be translated as “the power in the air,” which is not far from being an important part of the reality of the Ninth World–the dataweb that still exists around the planet (like the Internet, but times a million).
Specifically, though, in the setting, “the numenera” is a catch-all term for things from the past that pass understanding (things perceived by the mind but not the senses–experienced but not truly understood). Whether it’s a device that nullifies gravity, a bioengineered creature, a cloud of nanobots, a nearly indestructible metal, or something that allows one to see something going on miles away, it’s numenera.
That means, of course, that numenera is both beneficial and dangerous. Sometimes at the same time. Just like magic. Sir Clarke really knew what he was talking about.