Diomedea exulans vs mollymawk

Diomedea exulans and mollymawk both are nouns.

Word	Noun	Adjective	Verb	Adverb
Diomedea exulans	Yes	No	No	No
mollymawk	Yes	No	No	No

As nouns, mollymawk is a hypernym of Diomedea exulans; that is, mollymawk is a word with a broader meaning than Diomedea exulans:

Diomedea exulans: very large albatross; white with wide black wings
mollymawk: large web-footed birds of the Southern Hemisphere having long narrow wings; noted for powerful gliding flight

Other hypernyms of Diomedea exulans include albatross.

Diomedea exulans (noun)	mollymawk (noun)
very large albatross; white with wide black wings	large web-footed birds of the Southern Hemisphere having long narrow wings; noted for powerful gliding flight