sawbones vs Walter Reed

sawbones and Walter Reed both are nouns.

Word	Noun	Adjective	Verb	Adverb
sawbones	Yes	No	No	No
Walter Reed	Yes	No	No	No

sawbones (noun)	Walter Reed (noun)
a physician who specializes in surgery	United States physician who proved that yellow fever is transmitted by mosquitoes (1851-1902)