Ethereal – noun

Pertaining to the hypothetical upper, purer air, or to the higher regions beyond the earth or beyond the atmosphere; celestial; otherworldly; as, ethereal space; ethereal regions.

Consisting of ether; hence, exceedingly light or airy; tenuous; spiritlike; characterized by extreme delicacy, as form, manner, thought, etc.

Wiktionary Definition

My personal definition is (more or less): an elevated or alternate spiritual plane where we can glimpse truth or higher purposes. We can also find insights into our own existence, environments and the people that surround us. This includes our professional landscapes.

Historical

Wireshark, a packet capture and analyzer, used to be named Ethereal.