Related Clues:

• Greek letter in an early Christogram
• Greek "P"
• P, on campus
• Chi-___ (Christian symbol)
• Circular letter
• The end of Hector?
• Greek alphabet's 17th letter
• Xi follower
• Moronic sort of letter
• P's look-alike
• Letter in the Hammett equation
• P, in a 63-Across
• End of Hector?
• P on a frat pin
• P in Greece