The term "canary" can have multiple meanings depending on its context.
1) In a general sense, it refers to a small bird with yellow feathers that is often kept as a pet or used in singing competitions.
2) It may also refer to a type of safety equipment worn by miners while working underground. The canary was carried into the mine and its health would be monitored for any signs of dangerous gases. If the canary became sick, it indicated that there were unsafe conditions and the miners should evacuate immediately.
3) In a more figurative sense, "canary" may refer to someone who is sensitive or vulnerable in certain situations - often used when referring to women or children. For example, "She's such a canary, she gets scared easily."