Birgit Nilsson vs Nilsson

Birgit Nilsson and Nilsson both are nouns.

Word	Noun	Adjective	Verb	Adverb
Birgit Nilsson	Yes	No	No	No
Nilsson	Yes	No	No	No

As nouns, Birgit Nilsson and Nilsson are synonyms defined as:

Birgit Nilsson and Nilsson: Swedish operatic soprano who played Wagnerian roles (born in 1918)

Other synonyms of Birgit Nilsson include Brigit Nilsson, Marta Brigit Nilsson.

Birgit Nilsson (noun)	Nilsson (noun)
Swedish operatic soprano who played Wagnerian roles (born in 1918)	Swedish operatic soprano who played Wagnerian roles (born in 1918)