Possible Clues:

• Certain club restriction
• Ladies' club policy
• Only females getting this classical appellation
• Policy at certain clubs
• 'Julius' in Gaius Julius Caesar
• The 'Claudius' in Tiberius Claudius Nero
• Name, in Latin
• All-female group's policy
• Policy at a ladies' club
• The 'Julius' of Gaius Julius Caesar, e.g.