The term "crash" has several meanings, depending on its context.
1) In a general sense, it can refer to an abrupt and sudden event that disrupts normal operations or activity; for example, "the stock market crashed," meaning the value of stocks dropped rapidly.
2) It can also refer to a physical impact between two objects or vehicles resulting in damage or destruction; for instance, "a car crash."
3) In computer science, it refers to an error that causes a program to stop working correctly; this is known as a "crash" or "bug".