(Κάστωρ), either a native of Rhodes, of Massilia, or of Galatia, was a Greek grammarian and rhetorician, who was surnamed Φιλορώμαιος, and is usually believed to have lived about the time of Cicero and Julius Caesar.
[L.S]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890