Question

Real McCoy the genuine article; something of good quality, compared to others; not a fake or copy

Accepted Answer

That is a fake antique. This one's the real McCoy. There are two good possibilities as to this idiom's origin. One is a boxer in the late 1800s who called himself Kid McCoy. (His real name was Norman Selby.) He was a great fighter and so popular that other boxers started calling themselves Kid McCoy. So Mr. Selby had to bill himself as "the real McCoy." Other word experts trace this idiom to Elijah McCoy (1843–1929), an African-American inventor who was best known for inventing lubricating parts for steam engines.

Idiom	Real McCoy
Example	That is a fake antique. This one's the real McCoy.
Meaning	the genuine article; something of good quality, compared to others; not a fake or copy
Origin	There are two good possibilities as to this idiom's origin. One is a boxer in the late 1800s who called himself Kid McCoy. (His real name was Norman Selby.) He was a great fighter and so popular that other boxers started calling themselves Kid McCoy. So Mr. Selby had to bill himself as "the real McCoy." Other word experts trace this idiom to Elijah McCoy (1843–1929), an African-American inventor who was best known for inventing lubricating parts for steam engines.

Real Mccoy Fake Good Kid Antique One's Genuine