Definitions
1.adjectivePertaining to the hypothetical upper, purer air, or to the higher regions beyond the earth or beyond the atmosphere; celestial; otherworldly."ethereal space ethereal regions"
2.adjectiveConsisting of ether; hence, exceedingly light or airy; tenuous; spiritlike; characterized by extreme delicacy, as form, manner, thought, etc.
3.adjectiveDelicate, light and airy.
4.adjectiveTo do with ether."an ethereal solution"