porterhouse steak vs beefsteak

porterhouse steak and beefsteak both are nouns.

Word	Noun	Adjective	Verb	Adverb
porterhouse steak	Yes	No	No	No
beefsteak	Yes	No	No	No

As nouns, beefsteak is a hypernym of porterhouse steak; that is, beefsteak is a word with a broader meaning than porterhouse steak:

porterhouse steak: large steak from the thick end of the short loin containing a T-shaped bone and large piece of tenderloin
beefsteak: a beef steak usually cooked by broiling

porterhouse steak (noun)	beefsteak (noun)
large steak from the thick end of the short loin containing a T-shaped bone and large piece of tenderloin	a beef steak usually cooked by broiling