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Ptolemy

American  
[tol-uh-mee] / ˈtɒl ə mi /

noun

plural

Ptolemies
  1. Claudius Ptolemaeus, flourished a.d. 127–151, Hellenistic mathematician, astronomer, and geographer in Alexandria.

  2. any of the kings of the Macedonian dynasty that ruled Egypt 323–30 b.c.


Ptolemy British  
/ ˈtɒlɪmɪ /

noun

  1. Latin name Claudius Ptolemaeus. 2nd century ad , Greek astronomer, mathematician, and geographer. His Geography was the standard geographical textbook until the discoveries of the 15th century. His system of astronomy (see Ptolemaic system ), as expounded in the Almagest, remained undisputed until the Copernican system was evolved

"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

Ptolemy Scientific  
/ tŏlə-mē /
  1. Greek astronomer and mathematician who based his astronomy on the belief that all heavenly bodies revolved around Earth. Ptolemy's model of the solar system endured until the 16th century when Nicolaus Copernicus proposed that the heavenly bodies in the solar system orbited the Sun.


Ptolemy 1 Cultural  
  1. An ancient Greek astronomer, living in Egypt (see also Egypt), who proposed a way of calculating the movements of the planets on the assumption that they, along with the sun and the stars, revolved around the Earth. (See Ptolemaic universe.)


Ptolemy 2 Cultural  
  1. An ancient Greek astronomer, living in Egypt (see also Egypt), who proposed a way of calculating the movements of the planets on the assumption that they, along with the sun and the stars, were embedded in clear spheres that revolved around the Earth. The system of Ptolemy, called the Ptolemaic universe, prevailed in astronomy for nearly fifteen hundred years, until the modern model of the solar system, with the sun at the center and the planets in motion, was developed from the ideas of Copernicus.


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Memorable figures include the town barber and perpetual bachelor, Jayber Crow, and the Falstaffian 300-pound farmer Ptolemy Proudfoot, who lives happily with his diminutive wife, Miss Minnie.

From The Wall Street Journal • Oct. 23, 2025

Clausen believes the chart’s author conflated Ptolemy with a dynasty of Greek kings who had ruled Egypt.

From Los Angeles Times • Oct. 25, 2023

When he examined the map, he saw the figure was actually an homage to the 2nd century geographer Ptolemy.

From Los Angeles Times • Oct. 25, 2023

A few centuries later, another Greek astronomer, Ptolemy, attempted to classify stars using a six-tier scale, assigning the brightest stars to the first tier and the faintest ones to the sixth.

From Scientific American • Jul. 28, 2023

If della Porta happens to hold the same view as we do on the subject of garlic and magnets, it is not because he is better at handling evidence than Plutarch or Ptolemy.

From "The Invention of Science" by David Wootton