real McCoy, the

real McCoy, the

Also, the McCoy. The genuine thing, as in That painting's not a reproduction-it's the real McCoy. This idiom has a disputed origin, but the most likely source is its use to distinguish welterweight champion "Kid McCoy," the name used by Norman Selby (1873-1940), from other boxers using his name to capitalize on his popularity. [c. 1900]
See also: real
References in periodicals archive ?
After Furman had scored a shock 1-10 8-7 2-1 win, Price said, ``Instead of the Real McCoy, the world championship portable rink which we used at Potters in Norfolk last month, we have had to play here on a poor surface.