aspect vs countenance

aspect and countenance both are nouns.

Word	Noun	Adjective	Verb	Adverb
aspect	Yes	No	No	No
countenance	Yes	No	Yes	No

As nouns, countenance is a hypernym of aspect; that is, countenance is a word with a broader meaning than aspect:

Other hypernyms of aspect include visage.

aspect (noun)	countenance (noun)
the feelings expressed on a person's face	the appearance conveyed by a person's face
a characteristic to be considered	the human face (`kisser' and `smiler' and `mug' are informal terms for `face' and `phiz' is British)
a distinct feature or element in a problem	formal and explicit approval
the visual percept of a region
the beginning or duration or completion or repetition of the action of a verb

aspect (verb)	countenance (verb)
	consent to, give permission; permit