noun
or crystalline sphere
: either of two transparent spheres imagined in the Ptolemaic system of astronomy to exist between the region of the fixed stars and the primum mobile in order to explain certain observed movements of the heavenly bodies
noun
or crystalline sphere
: either of two transparent spheres imagined in the Ptolemaic system of astronomy to exist between the region of the fixed stars and the primum mobile in order to explain certain observed movements of the heavenly bodies
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012