The term "cage" has several meanings, depending on its context.
1) In a general sense, a cage refers to any enclosure or structure made up of bars, wires, or mesh that is used for confining an animal or keeping something safe and secure. For example, one might say “I put the bird in a cage” meaning they placed it inside an enclosed space where it cannot escape.
2) In another context, "cage" can refer to a type of protective gear worn during contact sports such as boxing or mixed martial arts. The fighter wears this gear which covers their body except for the arms and face in order to prevent injury while allowing them to move freely.
3) Finally, "cage" is also used colloquially to refer to a car, especially an old one that may be falling apart or not running well. For example, someone might say “I’m driving my cage to work today” meaning they are using their old and unreliable vehicle for transportation.