rollmops vs hors d'oeuvre

rollmops and hors d'oeuvre both are nouns.

Word	Noun	Adjective	Verb	Adverb
rollmops	Yes	No	No	No
hors d'oeuvre	Yes	No	No	No

As nouns, hors d'oeuvre is a hypernym of rollmops; that is, hors d'oeuvre is a word with a broader meaning than rollmops:

rollmops: a pickled herring filet that has been rolled or wrapped around a pickle
hors d'oeuvre: a dish served as an appetizer before the main meal

Other hypernyms of rollmops include pickled herring.

rollmops (noun)	hors d'oeuvre (noun)
a pickled herring filet that has been rolled or wrapped around a pickle	a dish served as an appetizer before the main meal