doggy vs Canis familiaris

doggy and Canis familiaris both are nouns.

Word	Noun	Adjective	Verb	Adverb
doggy	Yes	No	No	No
Canis familiaris	Yes	No	No	No

As nouns, Canis familiaris is a hypernym of doggy; that is, Canis familiaris is a word with a broader meaning than doggy:

doggy: informal terms for dogs
Canis familiaris: a member of the genus Canis (probably descended from the common wolf) that has been domesticated by man since prehistoric times; occurs in many breeds

Other hypernyms of doggy include dog, domestic dog.

doggy (noun)	Canis familiaris (noun)
informal terms for dogs	a member of the genus Canis (probably descended from the common wolf) that has been domesticated by man since prehistoric times; occurs in many breeds