pi
1 Americannoun
plural
pis-
the 16th letter of the Greek alphabet (Π, π).
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the consonant sound represented by this letter.
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Mathematics.
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the letter π, used as the symbol for the ratio of the circumference of a circle to its diameter.
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the ratio itself: 3.141592+.
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noun
plural
pies-
printing types mixed together indiscriminately.
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any confused mixture; jumble.
verb (used with object)
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to reduce (printing types) to a state of confusion.
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to jumble.
abbreviation
noun
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the 16th letter in the Greek alphabet (Π, π), a consonant, transliterated as p
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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
abbreviation
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Philippine Islands
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private investigator
adjective
noun
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a jumbled pile of printer's type
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a jumbled mixture
verb
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to spill and mix (set type) indiscriminately
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to mix up
Etymology
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
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
In science-fiction scenarios of first contact with extraterrestrials, humans usually bootstrap a common language with mathematics, demonstrating that we know the digits of pi and so forth.
In recent decades, advances in computing have pushed this familiar constant far beyond the classroom, with powerful supercomputers now calculating pi to trillions of decimal places.
From Science Daily
Classical computers have managed the calculation for molecules as large as pentacene, a chain of five hydrocarbon rings with 22 electrons in “pi” covalent bonds, which govern the molecule’s shape and reactivity.
From Science Magazine
That ratio is pi, which means the circumference is always going to be about 3.14 times as long as the diameter.
From NewsForKids.net
It’s the first Greek letter in the words “periphery” and “perimeter,” and pi is the ratio of a circle’s periphery — or circumference — to its diameter.
From Seattle Times
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
