Downing Street vs regime

Downing Street and regime both are nouns.

Word	Noun	Adjective	Verb	Adverb
Downing Street	Yes	No	No	No
regime	Yes	No	No	No

As nouns, regime is a hypernym of Downing Street; that is, regime is a word with a broader meaning than Downing Street:

Downing Street: the British government
regime: the organization that is the governing authority of a political unit

Other hypernyms of Downing Street include authorities, government.

Downing Street (noun)	regime (noun)
the British government	(medicine) a systematic plan for therapy (often including diet)
a street of Westminster in London	the organization that is the governing authority of a political unit