The term "ceilometer" refers to a device that is used to measure the height of clouds above the ground. There are several other terms that can be used to describe the same device, including cloud height indicator, sky scanner, cloud detector, and cloud base recorder. These devices are commonly used by pilots and meteorologists to determine cloud heights, which is vital information for aviation safety and weather forecasting. Regardless of the name used, they all serve the same essential function of providing accurate cloud height measurements to ensure safe flight operations and weather predictions.