Johnny Cash vs John Cash

Johnny Cash and John Cash both are nouns.

Word	Noun	Adjective	Verb	Adverb
Johnny Cash	Yes	No	No	No
John Cash	Yes	No	No	No

As nouns, Johnny Cash and John Cash are synonyms defined as:

Johnny Cash and John Cash: United States country music singer and songwriter (1932-2003)

Other synonyms of Johnny Cash include Cash.

Johnny Cash (noun)	John Cash (noun)
United States country music singer and songwriter (1932-2003)	United States country music singer and songwriter (1932-2003)