Rock

A player who plays very tight, not very creatively. He raises only with the best hands. A real rock is fairly predictable: if he raises you on the end, you can throw away just about anything but the nuts.

The hard, firm and stable parts of the earth's crust. A sound and solid mass, layer, or ledge of mineral matter inplace, and of such hardness and texture that it cannot be effectively loosened or broken down by a 6-pound drifting pick or by ripping in a single pass. Natural solid mineral matter occurring in large masses or fragments. Naturally formed, consolidated material composed of grains of one or more minerals.