Related Clues:

• Semicircles
• Arm bones
• Zones
• Math measurements
• Planetary paths
• Minute hands, essentially
• Pinball paths
• Wheel spokes, e.g.
• Rainbows
• They form central angles
• Parentheses, e.g.
• Spoke more than once?
• Pendulum paths
• Semidiameters
• They may be private