house cat vs Felis domesticus

house cat and Felis domesticus both are nouns.

Word	Noun	Adjective	Verb	Adverb
house cat	Yes	No	No	No
Felis domesticus	Yes	No	No	No

As nouns, house cat and Felis domesticus are synonyms defined as:

house cat and Felis domesticus: any domesticated member of the genus Felis

Other synonyms of house cat include domestic cat, Felis catus.

house cat (noun)	Felis domesticus (noun)
any domesticated member of the genus Felis	any domesticated member of the genus Felis