an ancient instrument consisting of an arrangement of rings, all of which are circles of the same sphere, used to show the relative positions of the celestial equator, ecliptic, and other circles on the celestial sphere.
Origin of armillary sphere
First recorded in 1550–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a model of the celestial sphere consisting of rings representing the relative positions of the celestial equator, ecliptic, etc, used by early astronomers for determining the positions of stars
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
An early astronomical device made of fixed and movable rings representing circles of the celestial sphere, such as the ecliptic and the celestial equator. It was used as early as the third century bce as both a teaching instrument and an observational tool.
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