Herr vs form of address

Herr and form of address both are nouns.

Word	Noun	Adjective	Verb	Adverb
Herr	Yes	No	No	No
form of address	Yes	No	No	No

As nouns, form of address is a hypernym of Herr; that is, form of address is a word with a broader meaning than Herr:

Herr: a German courtesy title or form of address for a man
form of address: an identifying appellation signifying status or function: e.g. `Mr.' or `General'

Other hypernyms of Herr include title, title of respect.

Herr (noun)	form of address (noun)
a German courtesy title or form of address for a man	an identifying appellation signifying status or function: e.g. `Mr.' or `General'
a German man; used before the name as a title equivalent to Mr in English