Two-bagger, for one is a term used in baseball to refer to a player who hits a double. A double is a type of HIT in which the batter hits the ball and is able to make it to second base before the fielders can get it. This type of HIT is considered to be more difficult than a single, which is when the batter is able to make it to first base. A two-bagger, for one, is a player who is able to HIT a double.