Word origin · etymology
Latin through French.
Latin obliquitas means slanting or being at an angle; here it names the tilt between equator and ecliptic.
How we know · epistemology
Astronomical geometry
The tilt is defined between two reference planes and varies with time. A model must specify mean or true obliquity; the number is not a measure of personal inclination.
Connected concepts
Terms used in this explanation
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Sources & provenance
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