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armillary sphere

American  

noun

Astronomy.
  1. 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.


armillary sphere British  

noun

  1. 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

armillary sphere Scientific  
/ ärmə-lĕr′ē,är-mĭlə-rē /
  1. 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.


Etymology

Origin of armillary sphere

First recorded in 1550–60

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Without a telescope, says Gysembergh, he must have used a sighting tube, known as a dioptra, or a mechanism called an armillary sphere.

From Scientific American

A crowded rink is a sweaty, wheeled armillary sphere.

From Washington Post

Static sculptures of Brahe’s so-called armillary sphere proliferate in public parks, but few if any allow for detailed measurements like the one in Santa Fe.

From Seattle Times

Ever heard of an armillary sphere, a radio latino or a theodolite?

From Washington Post

Some are obvious, such as the armillary sphere and quadrant, an architect’s plumb bob and carpenter’s square, a compass, and a pair of dividers.

From Scientific American