Manx cat vs house cat

Manx cat and house cat both are nouns.

Word	Noun	Adjective	Verb	Adverb
Manx cat	Yes	No	No	No
house cat	Yes	No	No	No

As nouns, house cat is a hypernym of Manx cat; that is, house cat is a word with a broader meaning than Manx cat:

Manx cat: a short-haired tailless breed of cat believed to originate on the Isle of Man
house cat: any domesticated member of the genus Felis

Other hypernyms of Manx cat include domestic cat, Felis catus, Felis domesticus.

Manx cat (noun)	house cat (noun)
a short-haired tailless breed of cat believed to originate on the Isle of Man	any domesticated member of the genus Felis