Summations : sigmas :: products : ___

• Letters on some college buildings
• Detectives like Magnum: Abbr
• Sorority letters
• Greek letters in geometry class
• Gumshoes, briefly
• Detectives, informally
• Trenchcoated antiheroes
• Gumshoes, for short
• TV's Rockford et al

Wikipedia Word definitions in Wikipedia
Pis is a commune in the Gers department in southwestern France .