What is Professional Surveying:

The application of knowledge of the science of surveying measurement, the legal principles of boundary location, the laws related to boundaries and land use, the applicable mathematical and computational theories and principles, the natural and other forces which affect positional accuracy, the land planning and development concepts pertinent to subdivision of land and property surveys, land record and land tenure concepts, geodetic and other earth-related sciences to the analsys, design, and execution of surveying and mapping projects and the design of land mapping and information systems.

What is Surveying Measurement

Surveying is the art, science and technology of gathering and analyzing measurement data related to the land and other land related surfaces and spaces, to include designing and devising the measurement specifications and standards to accomplish these measuremnts with the desired precision and accuracy and error control and adjustment, including the use of all instrumentation applicaple to such measuremnts, said measuremnts typically being, but not limited to distances, heights, angles, directions, positions, areas, volumes, and other measurements associated with these quantities.

Both definitions - Dr. Ben Buckner