Related Clues:

• Series-long story line
• Parabola, essentially
• Bow-shaped line
• Semicircular shape
• Go all around
• Long pass path
• Round figure
• Ellipse bit
• Compass trace
• Slow-pitch path
• Cissoid segment
• Plane path
• It can follow each word in 17-, 38- and 61-Across
• Circumference section
• There's simply no end to it