Ptolemaic system

noun

: 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

Word History

Etymology

after Ptolemy fl 2d century a.d. who maintained it

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