noun
geodesy
Scientific term for the measurement and representation of the Earth, including its gravitational field and geodynamic phenomena.
測地学は地球の形状や重力場を研究する学問です。
Geodesy is the science that studies the Earth's shape and gravitational field.
From 測地 (surveying/measuring the land) + 学 (study/science). The exact historical derivation is uncertain; the spelling is conventionally associated with the meaning of geodesy.