pi

¹

[ pahy ]

noun

, plural pis.

1. the 16th letter of the Greek alphabet (Π, π).
2. the consonant sound represented by this letter.
3. Mathematics.
   1. the letter π, used as the symbol for the ratio of the circumference of a circle to its diameter.
   2. the ratio itself: 3.141592+.

pi

²

or pie

[ pahy ]

noun

, plural pies.

1. printing types mixed together indiscriminately.
2. any confused mixture; jumble.

verb (used with object)

, pied, pi·ing.

1. to reduce (printing types) to a state of confusion.
2. to jumble.

PI

³

1. Law. personal injury.
2. principal investigator.
3. Also P.I., p.i. private investigator.

Pi.

⁴

or pi.

abbreviation for

1. piaster.

P.I.

⁵

abbreviation for

1. Philippine Islands.
2. Also PI, p.i. private investigator.

pi

¹

/ paɪ /

noun

1. a jumbled pile of printer's type
2. a jumbled mixture

verb

1. to spill and mix (set type) indiscriminately
2. to mix up

PI

²

abbreviation for

1. Philippine Islands
2. private investigator

pi

³

/ paɪ /

noun

1. the 16th letter in the Greek alphabet (Π, π), a consonant, transliterated as p
2. maths a transcendental number, fundamental to mathematics, that is the ratio of the circumference of a circle to its diameter. Approximate value: 3.141 592…; symbol: π

pi

⁴

/ paɪ /

adjective

1. slang.
   short for pious pious

pi

/ pī /

1. An irrational number that has a numerical value of 3.14159265358979… and is represented by the symbol π. It expresses the ratio of the circumference to the diameter of a circle and appears in many mathematical expressions.

pi

1. The irrational number obtained by dividing the length of the diameter of a circle into its circumference . Pi is approximately 3.1416. The sign for pi is π.

Word History and Origins

Origin of pi¹

First recorded in 1835–45; from Greek pî, peî, used in mathematics to represent Greek periphérion periphery ( def )

Origin of pi²

First recorded in 1650–60; origin uncertain

Word History and Origins

Origin of pi¹

C17: of uncertain origin

Origin of pi²

C18 (mathematical use): representing the first letter of Greek periphereia periphery

Example Sentences

“That’s an unusual way to start,” the “Magnum, P.I.” and “Blue Bloods” star admits in an interview.

From Seattle Times

Famously, his shooting schedule for “Magnum, P.I.” forced him to decline an offer to play Indiana Jones in “Raiders of the Lost Ark,” a part which went to Harrison Ford.

From Seattle Times

Portraits of other stars also make appearances, like Carol Burnett, Princess Diana and Frank Sinatra, whose last acting job was on “Magnum, P.I.” and who showed off his temper as well as his acting chops while navigating a colostomy bag.

From Seattle Times

With a bat of her eyelashes, the poolman becomes a P.I.

From Los Angeles Times

Post, whose catalog of TV music spans six decades and includes such hit shows as “Hill Street Blues,” “Magnum, P.I.,”

From Los Angeles Times

Related Words

• inquiry agent
• P.I.
• private detective
• private dick
• private eye
• private investigator
• sleuth