Earth & SkyGreek → English
Geodesy
/dʒiˈɒdɪsi/noun
The science of measuring the shape and size of the Earth and fixing positions on it.
The Greek roots
γῆ
gê
earth, land
δαίομαι
daíomai
to divide
Literally: “dividing the earth”
The story of the word
Aristotle drew a line between γεωμετρία, which reasons about ideal figures, and γεωδαισία, which is the arithmetic of splitting an actual field between actual heirs. The modern discipline began with an argument: Newton predicted the Earth bulges at the equator, Cassini's measurements suggested the opposite, and France sent expeditions to Lapland and Peru in the 1730s to settle it. Newton was right.
- How it travelled
- Ancient Greek → Latin → English
- First recorded
- 16th century
Same family
geometrygeographygeologygeoid
In a sentence
Satellite geodesy can now track the ground rising as an ice sheet melts off it.