Pi (disambiguation)

Pi (math), , or π, is the mathematical constant equal to a circle's circumference divided by its diameter.

Pi may also refer to:
Letter Pi (π)
Pi (letter), the Greek letter
Lowercase π:
 π (film), a 1998 film directed by Darren Aronofsky
  (pi function), the prime-counting function
 Pi bond
 Osmotic pressure
 A song from the Kate Bush album Aerial
 Shorthand for pion
 A men's fragrance from Givenchy
 The symbol for political life used in Boethius' Consolation of Philosophy
Uppercase Π:
 The product symbol
  (Pi function), the Gamma function when offset to coincide with the factorial
 , the reciprocal of the Pi function

Pi as a word
 Pi (instrument)
 Pi (.hack), a fictional character from the multimedia franchise .hack//G.U.
 Pi Magazine
 Pi Recordings, a record label
 "Pi", a song from the Hard 'n Phirm album Horses and Grasses; the song ends at 3:14
 Pi, a member of Team Robo in Sega Soccer Slam
 Pi, a fictional character in the novel Life of Pi
 Pi County, county in Sichuan, China