SINCE 1828
Ptolemaic system
nounDefinition of Ptolemaic system
: the system of planetary motions according to which the earth is at the center with the sun, moon, and planets revolving around it and each orbit except for the sun and moon is composed of a principal circle upon which moves a smaller circle carrying the planet — compare copernican system, deferent, eccentric entry 2 sense 2, epicycle
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