diurnal motion

noun Astronomy.
the apparent daily motion, caused by the earth's rotation, of celestial bodies across the sky.
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diurnal motion
 
n
motion that occurs during the day or daily, such as the diurnal rotation of the celestial sphere

Collins English Dictionary - Complete & Unabridged 10th Edition
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Encyclopedia Britannica
Encyclopedia

diurnal motion

apparent daily motion of the heavens from east to west in which celestial objects seem to rise and set, a phenomenon that results from the Earth's rotation from west to east. The axis of this apparent motion coincides with the Earth's axis of rotation. The intersection of the plane of the Earth's Equator with the celestial sphere defines the celestial equator. The apparent daily paths of celestial objects are circles parallel to the celestial equator and are termed diurnal circles

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Example sentences
It is disorienting both because of dark and bright juxtapositions and the discontinuities in the diurnal motion.
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