A quarry can mean two very different things:

1. A large open pit where workers dig stone, marble, or minerals out of the earth. Ancient builders cut massive blocks of limestone from quarries to construct the pyramids of Egypt. Modern quarries supply stone for buildings, roads, and sculptures. Workers use heavy machinery to break rock free from the earth, creating deep holes that can stretch for acres. Some abandoned quarries fill with water and become swimming holes, though this can be dangerous because quarry walls are often steep and unstable.
2. An animal being hunted or chased. When a hawk spots a mouse in a field, that mouse becomes the hawk's quarry. In adventure stories, a detective might track their quarry through city streets, or a medieval hunter might pursue their quarry through the forest. The word suggests active pursuit: the quarry is trying to escape while the hunter or predator follows. You might read that “the fox eluded its pursuers” or “the spy lost their quarry in the crowded marketplace.”