Sublime Porte vs royal court

Sublime Porte and royal court both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sublime Porte	Yes	No	No	No
royal court	Yes	No	No	No

As nouns, royal court is a hypernym of Sublime Porte; that is, royal court is a word with a broader meaning than Sublime Porte:

Sublime Porte: the Ottoman court in Constantinople
royal court: the sovereign and his advisers who are the governing power of a state

Other hypernyms of Sublime Porte include court.

Sublime Porte (noun)	royal court (noun)
the Ottoman court in Constantinople	the sovereign and his advisers who are the governing power of a state
	the family and retinue of a sovereign or prince