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pi1

[pahy] /paɪ/
noun, plural pis.
1.
the 16th letter of the Greek alphabet (II, 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+.
Origin
1835-1845
1835-45; < Greek pî, peî; used in mathematics to represent Greek periphérion periphery

pi2

[pahy] /paɪ/
noun, plural pies.
1.
printing types mixed together indiscriminately.
2.
any confused mixture; jumble.
verb (used with object), pied, piing.
3.
to reduce (printing types) to a state of confusion.
4.
to jumble.
Also, pie.
Origin
1650-60; origin uncertain

PI

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

Pi.

1.
Also, pi.

P.I.

1.
Philippine Islands.
2.
Also, PI, p.i. private investigator.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples from the web for pi
  • Area enclosed the area enclosed by a circle is the radius squared, multiplied by pi.
British Dictionary definitions for pi

pi1

/paɪ/
noun (pl) pis
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
Word Origin
C18 (mathematical use): representing the first letter of Greek periphereiaperiphery

pi2

/paɪ/
noun (pl) pies
1.
a jumbled pile of printer's type
2.
a jumbled mixture
verb (transitive) pies, piing, pied, pies, pieing, pied
3.
to spill and mix (set type) indiscriminately
4.
to mix up
Word Origin
C17: of uncertain origin

pi3

/paɪ/
adjective
1.
(Brit, slang) short for pious (sense 2), pious (sense 3)

PI

abbreviation
1.
Philippine Islands
2.
private investigator
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for pi
n.

Greek letter, from Hebrew, literally "little mouth." As the name of the mathematical constant, from 1841 in English, used in Latin 1748 by Swiss mathematician Leonhart Euler (1707-1783), as an abbreviation of Greek periphereia "periphery." For the meaning "printer's term for mixed type," see pie (3).

Online Etymology Dictionary, © 2010 Douglas Harper
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pi in Medicine

pi (pī)
n. pl. pis

Symbol π The 16th letter of the Greek alphabet.

pI (pē'ī')
n.
The pH value for the isoelectric point of a given substance in solution.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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pi in Science
pi
  (pī)   
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.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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pi in Culture
pi [(peye)]

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.

The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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Slang definitions & phrases for pi

PI

noun
  1. A pimp (1931+)
  2. A private detective; op (1960+)

The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D.
Copyright (C) 2007 by HarperCollins Publishers.
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pi in Technology

An interface between Prolog application programs and the X Window System that aims to be independent from the Prolog engine, provided that it has a Quintus foreign function interface (e.g. SICStus and YAP). It is mostly written in Prolog and is divided in two libraries: Edipo - the lower level interface to the Xlib functions; and Ytoolkit - the higher level user interface toolkit.
(ftp://ftp.ncc.up.pt/pub/prolog/ytoolkit.tar.Z).
E-mail: Ze' Paulo Leal .
(1993-03-02)
The Free On-line Dictionary of Computing, © Denis Howe 2010 http://foldoc.org
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Related Abbreviations for pi

pi

Pali

Pi

inorganic phosphate

PI

  1. performance indicator
  2. politically incorrect
  3. present illness
  4. primary infertility
  5. principal investigator
  6. private investigator
The American Heritage® Abbreviations Dictionary, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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4
5
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