geodesy

noun

Etymology: From French géodésie, from Medieval Latin geōdaesia, from Ancient Greek γεωδαισία (geōdaisía), from γῆ (gê, “earth”) + δαίω (daíō, “to divide”). By surface analysis, geode + -esy.

1. The discipline which deals with the measurement and representation of Earth, its gravitational field and geodynamic phenomena (polar motion, Earth tides, and crustal motion) in three-dimensional, time-varying space.