Quai d'Orsay vs Foreign Office

Quai d'Orsay and Foreign Office both are nouns.

Word	Noun	Adjective	Verb	Adverb
Quai d'Orsay	Yes	No	No	No
Foreign Office	Yes	No	No	No

As nouns, Foreign Office is a hypernym of Quai d'Orsay; that is, Foreign Office is a word with a broader meaning than Quai d'Orsay:

Quai d'Orsay: the French department in charge of foreign affairs; referred to familiarly by its address in Paris
Foreign Office: the government department in charge of foreign relations

Quai d'Orsay (noun)	Foreign Office (noun)
the French department in charge of foreign affairs; referred to familiarly by its address in Paris	the government department in charge of foreign relations
the street in Paris along the south bank of the Seine known for its governmental ministries