When English speakers first borrowed the Greek word katastrophē (from katastrephein, meaning “to overturn”) it involved describing a catastrophe in the 1500s, where they used it for the conclusion or final event of a dramatic work, especially a tragedy. In time, catastrophe came to be used more generally of any unhappy conclusion, or disastrous or ruinous end. By the mid-18th century, catastrophe was used to describe a truly devastating event, such as an earthquake or a volcanic eruption. (Merriam-Webster)

In today’s world of insurance restoration, a catastrophe or catastrophic event (CAT) is a sudden and often violent event, which is either natural or manmade, that is unusually severe, where property damage exceeds $25 million dollars. (III)