GIMMIE
A putt that one player requests be conceded by another player, allowing the first player to pick up and move on as if the putt had been holed. The word derives from "give me," as in, "Will you give me that one?" Many golfers play using gimmies for any short putt.
The usage confusion here is with the term "inside the leather" which refers to the distance required in most instances for a putt to be considered a gimmie. Because "inside the leather" is the main characteristic of a gimmie, many will use the terms incorrectly.
GROSS SCORE
Gross score refers to the total number of strokes taken during your round of golf, plus any penalty strokes. In other words, your total score without adjustments. Add up the numbers on your scorecard at the end of the round, and that's your gross score.
Commonly confused with "net score" as both refer to a golfer's score, just in different ways.