grampus vs Orcinus orca

grampus and Orcinus orca both are nouns.

Word	Noun	Adjective	Verb	Adverb
grampus	Yes	No	No	No
Orcinus orca	Yes	No	No	No

As nouns, grampus and Orcinus orca are synonyms defined as:

grampus and Orcinus orca: predatory black-and-white toothed whale with large dorsal fin; common in cold seas

Other synonyms of grampus include killer, killer whale, orca, sea wolf.

grampus (noun)	Orcinus orca (noun)
slaty-grey blunt-nosed dolphin common in northern seas	predatory black-and-white toothed whale with large dorsal fin; common in cold seas
predatory black-and-white toothed whale with large dorsal fin; common in cold seas