geodesy

n. branch of science dealing with the measurement of land and determination of geographical points

Geodesy (IPA North American English ; British, Australian English etc. ), also called geodetics, a branch of earth sciences, is the scientific discipline that deals with the measurement and representation of the Earth, including its gravity field, in a three-dimensional time varying space. Besides the Earth's gravity field, geodesists study also geodynamical phenomena such as crustal motion, tides, and polar motion. For this they design global and national Control networks, using Space and terrestrial techniques while relying on datums and coordinate systems.
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Noun
1. the branch of geology that studies the shape of the earth and the determination of the exact position of geographical points
(hypernym) geophysics, geophysical science

(n.)
That branch of applied mathematics which determines, by means of observations and measurements, the figures and areas of large portions of the earth's surface, or the general figure and dimenshions of the earth; or that branch of surveying in which the curvature of the earth is taken into account, as in the surveys of States, or of long lines of coast.
  

Science concerned with the measurement and mathematical description of the size and shape of the earth and its gravitational fields. Geodesy also includes the large-scale, extended surveys for determining positions and elevations of points, in which the size and shape of the earth must be taken into account.