What is the definition of "bathymetry"?

Bathymetry is the measurement of the depth of bodies of water, including oceans, seas, lakes and rivers. Bathymetry may also refer to the shapes and features of underwater terrain, generally for use in a topographical map of the "bed" or "floor" of a body of water.

The word "bathymetry" is derived from Greek "bathus," meaning "deep," and "metron," meaning "measure." Bathymetry forms the foundation for the science of hydrography, the study of the physical features of a body of water. Bathymetric data is important in many fields, including biological oceanography and climate science. Bathymetric maps are also used to create nautical charts.