# pi

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## PI

*abbr.*

private investigator

## pi^{ 1}

(pī)*n.*

**2.**

*Mathematics*A transcendental number, approximately 3.14159, represented by the symbol π, that expresses the ratio of the circumference to the diameter of a circle and appears as a constant in many mathematical expressions.

## pi^{ 2}

also **pie**(pī)

*Printing*

*n.*

*pl.*

**pis**also

**pies**

An amount of type that has been jumbled or thrown together at random.

*v.*

**pied**(pīd),

**pi·ing**,

**pies**also

**pied**,

**pie·ing**,

**pies**

*v.*

*tr.*

To jumble or mix up (type).

*v.*

*intr.*

To become jumbled.

[

*Origin unknown*.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

## pi

(paɪ)*n*,

*pl*

**pis**

**1.**(Letters of the Alphabet (Foreign)) the 16th letter in the Greek alphabet (Π, π), a consonant, transliterated as

*p*

**2.**(Mathematics)

*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

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

*periphereia*periphery]## pi

(paɪ)*or*

## pie

*n*,

*pl*

**pies**

**1.**(Printing, Lithography & Bookbinding) a jumbled pile of printer's type

**2.**a jumbled mixture

*vb*(

*tr*) ,

**pies**,

**piing**,

**pied**,

**pies**,

**pieing**

*or*

**pied**

**3.**(Printing, Lithography & Bookbinding) to spill and mix (set type) indiscriminately

**4.**to mix up

[C17: of uncertain origin]

## pi

(paɪ)## PI

*abbreviation for*

**1.**(Placename) Philippine Islands

**2.**(Law) private investigator

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

## pi^{1}

(paɪ) *n.,*

*pl.*

**pis.**

**1.**the 16th letter of the Greek alphabet (Π, π).

**2.**

**a.**the letter π, used as the symbol for the ratio of the circumference of a circle to its diameter.

**b.**the ratio itself: 3.14159 +.

[1835–45; < Greek

*pî, peî;*used in math to represent Greek*periphérion*periphery]## pi^{2}

## or pie

(paɪ)*n.,*

*pl.*

**pies,**

*n.*

**1.**printing type mixed together indiscriminately.

**2.**any confused mixture; jumble.

*v.t.*

**3.**to jumble (printing type).

**4.**to mix up; jumble.

[1650–60; orig. uncertain]

## P.I.

Philippine Islands.

Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

## pi

(pī) An irrational number that has a numerical value of 3.14159265359... and is represented by the symbol π. It expresses the ratio of the circumference to the diameter of a circle and appears as a constant in many mathematical expressions.

The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

## pi

**Past participle:**pied

**Gerund:**piing

Imperative |
---|

pi |

pi |

Collins English Verb Tables © HarperCollins Publishers 2011

## pi

(") Symbol and name representing the ratio of a circle’s circumference to its diameter. Its value is approximately 3.14.

Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited

ThesaurusAntonymsRelated WordsSynonyms

**Legend:**Switch to new thesaurus

Noun | 1. | pi - the ratio of the circumference to the diameter of a circle; approximately equal to 3.14159265358979323846...transcendental number - an irrational number that is not algebraic |

2. | PI - someone who can be employed as a detective to collect informationdetective - an investigator engaged or employed in obtaining information not easily available to the public hotel detective, house detective - a private detective employed by a hotel or retail store inquiry agent - a private detective store detective - a private detective employed by a merchant to stop pilferage | |

3. | PI - the scientist in charge of an experiment or research projectscientist - a person with advanced knowledge of one or more sciences | |

4. | pi - the 16th letter of the Greek alphabetGreek alphabet - the alphabet used by ancient Greeks alphabetic character, letter of the alphabet, letter - the conventional characters of the alphabet used to represent speech; "his grandmother taught him his letters" | |

5. | PI - an antiviral drug used against HIV; interrupts HIV replication by binding and blocking HIV protease; often used in combination with other drugsdrug cocktail, HAART, highly active antiretroviral therapy - a combination of protease inhibitors taken with reverse transcriptase inhibitors; used in treating AIDS and HIV nelfinavir, Viracept - a protease inhibitor (trade name Viracept) used in treating HIV usually in combination with other drugs Invirase, saquinavir - a weak protease inhibitor (trade name Invirase) used in treating HIV |

Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.

Translations

**pí**

**erikoismerkki**

**pii**

**pí**

**pí**

**pi**

**pi**

## pi

[paɪ]*N*(

**pis (**) (

*pl*)*Math*) → pi

*f*

Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007

Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995

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