[ hi-pahr-kuh s ]
/ hɪˈpɑr kəs /


died 514 b.c., tyrant of Athens 527–514.
c190–c125 b.c., Greek astronomer.
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Examples from the Web for hipparchus

British Dictionary definitions for hipparchus (1 of 2)

/ (hɪˈpɑːkəs) /


2nd century bc, Greek astronomer. He discovered the precession of the equinoxes, calculated the length of the solar year, and developed trigonometry
died 514 bc, tyrant of Athens (527–514)

British Dictionary definitions for hipparchus (2 of 2)

/ (hɪˈpɑːkəs) /


a large crater in the SW quadrant of the moon, about 130 kilometres in diameter
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for hipparchus

also Hipparchos (hĭ-pärkəs) 190?-120? bce

Greek astronomer who mapped the positions of about 850 stars in the earliest known star chart (129 bce). His observations of the heavens formed the basis of Ptolemy's Earth-centered model of the universe. He was also a pioneer of trigonometry.
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