McCoy
Concise Oxford English Dictionary © 2008 Oxford University Press:
McCoy/məˈkɔɪ/
▶noun (in phr. the real McCoy) informal the real thing; the genuine article.
– origin C19: origin uncertain: perh. from the real Mackay, an advertising slogan used by the whisky distillers G. Mackay and Co.; the form McCoy may come from the name of the American inventor Elijah McCoy.
'McCoy' also found in these Oxford entries:
