common rorqual vs rorqual

common rorqual and rorqual both are nouns.

Word	Noun	Adjective	Verb	Adverb
common rorqual	Yes	No	No	No
rorqual	Yes	No	No	No

As nouns, rorqual is a hypernym of common rorqual; that is, rorqual is a word with a broader meaning than common rorqual:

common rorqual: large flat-headed whalebone whale having deep furrows along the throat; of Atlantic and Pacific
rorqual: any of several baleen whales of the family Balaenopteridae having longitudinal grooves on the throat and a small pointed dorsal fin

Other hypernyms of common rorqual include razorback.

common rorqual (noun)	rorqual (noun)
large flat-headed whalebone whale having deep furrows along the throat; of Atlantic and Pacific	any of several baleen whales of the family Balaenopteridae having longitudinal grooves on the throat and a small pointed dorsal fin