the definision of a rock is as follows,
n.
1. Relatively hard, naturally formed mineral or petrified matter; stone.
2.
a. A relatively small piece or fragment of such material.
b. A relatively large body of such material, as a cliff or peak.
3. A naturally formed aggregate of mineral matter constituting a significant part of the earth's crust.
4. One that is similar to or suggestive of a mass of stone in stability, firmness, or dependability: The family has been his rock during this difficult time.
5. rocks Slang Money.
6. Slang A large gem, especially a diamond.
7. Slang Crack cocaine.
8.
a. A varicolored stick candy.
b. Rock candy.