beef vs corn beef

beef and corn beef both are nouns.

Word	Noun	Adjective	Verb	Adverb
beef	Yes	No	Yes	No
corn beef	Yes	No	No	No

As nouns, corn beef is a hyponym of beef; that is, corn beef is a word with a more specific, narrower meaning than beef:

Other hyponyms of beef include ground beef, hamburger, bully beef, corned beef, pastrami.

beef (noun)	corn beef (noun)
cattle that are reared for their meat	beef cured or pickled in brine
informal terms for objecting
meat from an adult domestic bovine

beef (verb)	corn beef (verb)
complain