from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A photoelectric instrument for ascertaining cloud heights.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A device that measures the altitude of the cloud base, especially above an airfield
The British also had developed a device called a ceilometer, which triangulated ultraviolet rays to calculate how low clouds were over the three Berlin airports.
Vaisala launches new ceilometer for high range cloud detection
The Remote Miniature Weather Station (RMWS), from System Innovations, is an air-droppable version with a lightweight, expendable and modular system comprised of two components; a meteorological (MET) sensor and a ceilometer (cloud ceiling height) with limited MET.