pi

1
[ pahy ]
/ paɪ /

noun, plural pis.

the 16th letter of the Greek alphabet (II, π).
the consonant sound represented by this letter.
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+.

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Origin of pi

1
1835–45; < Greek pî, peî; used in mathematics to represent Greek periphérion periphery

Definition for pis (2 of 2)

pi2

or pie

[ pahy ]
/ paɪ /

noun, plural pies.

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

verb (used with object), pied, pi·ing.

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

Origin of pi

2
First recorded in 1650–60; origin uncertain
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for pis

British Dictionary definitions for pis (1 of 4)

PI

abbreviation for

Philippine Islands
private investigator

British Dictionary definitions for pis (2 of 4)

pi1
/ (paɪ) /

noun plural pis

the 16th letter in the Greek alphabet (Π, π), a consonant, transliterated as p
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 for pi

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

British Dictionary definitions for pis (3 of 4)

pi2

pie

/ (paɪ) /

noun plural pies

a jumbled pile of printer's type
a jumbled mixture

verb pies, piing, pied, pies, pieing or pied (tr)

to spill and mix (set type) indiscriminately
to mix up

Word Origin for pi

C17: of uncertain origin

British Dictionary definitions for pis (4 of 4)

pi3
/ (paɪ) /

adjective

British slang short for pious (def. 2), pious (def. 3)
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

Medical definitions for pis (1 of 2)

pi
[ pī ]

n. pl. pis

The 16th letter of the Greek alphabet.

Medical definitions for pis (2 of 2)

pI
[ pēī ]

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.

Scientific definitions for pis

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 © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for pis

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 New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.