ether vs ethereal

ether is a noun but ethereal is not a noun.

Word	Noun	Adjective	Verb	Adverb
ether	Yes	No	No	No
ethereal	No	Yes	No	No

ether (noun)	ethereal (noun)
a colorless volatile highly flammable liquid formerly used as an inhalation anesthetic
a medium that was once supposed to fill all space and to support the propagation of electromagnetic waves
any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom
the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies

ether (adjective)	ethereal (adjective)
	of or containing or dissolved in ether
	characterized by unusual lightness and delicacy
	of heaven or the spirit
	characterized by lightness and insubstantiality; as impalpable or intangible as air