Crossword clues for epicycle
epicycle
The Collaborative International Dictionary
Epicycle \Ep"i*cy`cle\, n. [L. epicyclus, Gr. ?; 'epi` upon + ? circle. See Cycle.]
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(Ptolemaic Astron.) A circle, whose center moves round in the circumference of a greater circle; or a small circle, whose center, being fixed in the deferent of a planet, is carried along with the deferent, and yet, by its own peculiar motion, carries the body of the planet fastened to it round its proper center.
The schoolmen were like astronomers which did feign eccentrics, and epicycles, and such engines of orbs.
--Bacon. (Mech.) A circle which rolls on the circumference of another circle, either externally or internally.
Douglas Harper's Etymology Dictionary
Wiktionary
n. 1 (context astronomy English) A small circle whose centre is on the circumference of a larger circle; in Ptolemaic astronomy it was seen as the basis of revolution of the "seven planets", given a fixed central Earth. 2 (context mathematics English) Any circle whose circumference rolls around that of another circle, thus creating a hypocycloid or epicycloid.
WordNet
n. a circle that rolls around (inside or outside) another circle; generates an epicycloid or hypocycloid
Usage examples of "epicycle".
If you go once around the epicycle while the deferent rotates once, you trace out the ellipse.
He wears the Aristotelian cosmology like a shackle, clings to it like a wet-nurse, feeds upon its milk of false assumptions, and postulates the most unlikely machinery of epicycle, deferent, and equant.
But if I am no moth-eaten alchemist, neither am I some newfangled astronomer who feigns eccentrics and epicycles and suchlike in order to save the phenomena, when he knows full well that there are no such engines within the orbs.
For one thing, their astronomers have created an elaborate system of epicycles to account for the movements of the planets.
She faltered, remembering how quickly others got bored when she got caught up in cycles and epicycles, conjunctions and precession, the endlessly intriguing wonder of the universe.
The virus was endemic during two periods of the Helliconian year, in the Spring and in the late Autumn of the Great Year, with minor epicycles between these cycles.
But when it came to almagest and astrolabe, the counting of figures and reckoning of epicycles, away would go her thoughts to horse and hound, and a vacant eye and listless face would warn the teacher that he had lost his hold upon his scholar.
But I have heard it said that if the earth turns and all the planets, and the sun stands still, many phenomena are explained, whereas Ptolemy had to invent epicycles and deferents and all sorts of other stupidities that do not exist on earth or in heaven.
He tried to imagine fixed stars and wandering stars, spheres and epicycles, all these words that Liath used so easily—.
He tried to imagine fixed stars and wandering stars, spheres and epicycles, all these words that Liath used so easilybut it only made him impatient.
He tried to imagine fixed stars and wandering stars, spheres and epicycles, all these words that Liath used so easily-but it only made him impatient.
Ptolemy showed that if the epicycle turned roughly once a year, and were the appropriate size, the resulting apparent motion would show the correct retrograde motion.