1. (

• Ptolemy ,
• Claudius_Ptolemaeus

) Alexandrian astronomer (of the 2nd century) who proposed a geocentric system of astronomy that was undisputed until the late Renaissance ;

2. (

• Ptolemy ,
• Ptolemaic_dynasty

) an ancient dynasty of Macedonian kings who ruled Egypt from 323 BC to 30 BC; founded by Ptolemy I and ended with Cleopatra ;