Jimmy Cagney vs Cagney

Jimmy Cagney and Cagney both are nouns.

Word	Noun	Adjective	Verb	Adverb
Jimmy Cagney	Yes	No	No	No
Cagney	Yes	No	No	No

As nouns, Jimmy Cagney and Cagney are synonyms defined as:

Jimmy Cagney and Cagney: United States film actor known for his portrayals of tough characters (1899-1986)

Other synonyms of Jimmy Cagney include James Cagney.

Jimmy Cagney (noun)	Cagney (noun)
United States film actor known for his portrayals of tough characters (1899-1986)	United States film actor known for his portrayals of tough characters (1899-1986)