a combining form of sphere (planisphere); having a special use in the names of the layers of gases and the like surrounding the earth and other celestial bodies (ionosphere).
Seventh Heaven: Decoding the days of the week
For almost 2000 years—from the time of Aristotle until the early 17th century—popular theory posited that the earth was the center of the universe, and that everything in space rotated around it in concentric spheres filled with a heavenly fifth element called quintessence. Astronomers believed that the turning of these spheres accounted for the orbits of the heavenly bodies, and that they moved to the …
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Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
n combining form
having the shape or form of a spherebathysphere
indicating a spherelike enveloping massatmosphere
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