Prey refers to animals that are hunted and eaten by other animals. A mouse is prey for an owl. A zebra is prey for a lion. Rabbits, fish, and insects all serve as prey for various predators in nature.

In nature, prey animals have developed remarkable defenses. Rabbits can sprint and zigzag. Deer have keen hearing and can leap over obstacles. Many prey animals live in herds or flocks, where many eyes watch for danger and confusion makes it harder for predators to target individuals.

The word also works as a verb: to prey on something means to hunt it. Sharks prey on fish and seals. The phrase to fall prey to means to become a victim of something, not just in nature: you might fall prey to a clever scam or a persistent illness.

When someone preys on the vulnerable, they're taking advantage of people who can't easily defend themselves, like a bully picking on smaller kids. This use of the word connects the predator-prey relationship to human behavior.