alsatian vs sheep dog

alsatian and sheep dog both are nouns.

Word	Noun	Adjective	Verb	Adverb
alsatian	Yes	No	No	No
sheep dog	Yes	No	No	No

As nouns, sheep dog is a hypernym of alsatian; that is, sheep dog is a word with a broader meaning than alsatian:

alsatian: breed of large shepherd dogs used in police work and as a guide for the blind
sheep dog: any of various usually long-haired breeds of dog reared to herd and guard sheep

Other hypernyms of alsatian include sheepdog, shepherd dog.

alsatian (noun)	sheep dog (noun)
breed of large shepherd dogs used in police work and as a guide for the blind	any of various usually long-haired breeds of dog reared to herd and guard sheep