guinea pig vs Cavia cobaya

guinea pig and Cavia cobaya both are nouns.

Word	Noun	Adjective	Verb	Adverb
guinea pig	Yes	No	No	No
Cavia cobaya	Yes	No	No	No

As nouns, guinea pig and Cavia cobaya are synonyms defined as:

guinea pig and Cavia cobaya: stout-bodied nearly tailless domesticated cavy; often kept as a pet and widely used in research

guinea pig (noun)	Cavia cobaya (noun)
stout-bodied nearly tailless domesticated cavy; often kept as a pet and widely used in research	stout-bodied nearly tailless domesticated cavy; often kept as a pet and widely used in research
a person who is subjected to experimental or other observational procedures; someone who is an object of investigation