K2 vs Mount Godwin Austen

K2 and Mount Godwin Austen both are nouns.

Word	Noun	Adjective	Verb	Adverb
K2	Yes	No	No	No
Mount Godwin Austen	Yes	No	No	No

As nouns, K2 and Mount Godwin Austen are synonyms defined as:

K2 and Mount Godwin Austen: a mountain peak in the Karakoram Range in northern Kashmir; the 2nd highest peak in the world (28,250 feet high)

Other synonyms of K2 include Dapsang, Godwin Austen.

K2 (noun)	Mount Godwin Austen (noun)
a mountain peak in the Karakoram Range in northern Kashmir; the 2nd highest peak in the world (28,250 feet high)	a mountain peak in the Karakoram Range in northern Kashmir; the 2nd highest peak in the world (28,250 feet high)