A reg in poker is a player who is regularly playing. Because of this, a reg is usually an above-average poker player. A reg is the opposite of a rec, a player who plays primarily for fun and generally isn’t as skilled or experienced as a reg.
Reg Poker Example:
The poker term reg is mostly used in the context of a winning player. For example, a player who plays every day and wins most of the time is a reg, while a player who plays regularly and mostly loses is called a regfish.