Definition
Also known as "in the leather", this golf term is used in recreational golf where your playing partner "gives you the putt". When it is "in the leather", that refers to the distance between your ball and the hole being within the leather of your putter grip. In other words, since it's a short putt (typically less than 3 feet), your playing partner assumes you will make it, so you don't have to putt it. In professional and competitive golf, there is no such thing as a gimme. No matter how short the putt, you have to hit it.
Usage
C'mon, that putt is less than a foot, it's a gimme!