cup of joe

A cup of coffee. Though the true origin is unknown, "joe" as a synonym for coffee is theorized to either be a shortening of "jamoke" (a combination of Java and Mocha, two major suppliers of coffee beans), or as a reference to it being the drink of the ordinary man (i.e., the "average joe"). Primarily heard in US. I can't even function in the morning until I've had my first cup of joe. If you ask me, this place serves the best cup of joe in the whole city. The boss still hasn't finished his first cup of joe, so don't give him the bad news just yet.