pi

noun \ ˈpī \

Definition of pi

plural pis play \ˈpīz\

1 : the 16th letter of the Greek alphabet — see Alphabet Table

2 a : the symbol π denoting the ratio of the circumference of a circle to its diameter

b : the ratio itself : a transcendental number having a value rounded to eight decimal places of 3.14159265

Origin and Etymology of pi

Middle Greek, from Greek pei, of Semitic origin; akin to Hebrew pē pe

NEW! Time Traveler

First Known Use: 15th century

in the meaning defined at sense 1

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Other Alphabet Terms

cuneiform, linear, minuscule, pictograph, rune, symbology, wedge

pi

noun \ ˈpī \

variants: or less commonly pie

Definition of pi

plural pies

1 : type that is spilled or mixed

2 : a pi character or matrix

Origin and Etymology of pi

origin unknown

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First Known Use: circa 1659

in the meaning defined at sense 1

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pi

verb

variants: or less commonly pie

Definition of pi

pied; piing or pieing

transitive verb

: to spill or throw (type or type matter) into disorder

intransitive verb

: to become pied

First Known Use of pi

1889

in the meaning defined at transitive sense

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pi

adjective

variants: or less commonly pie

Definition of pi

1 : not intended to appear in final printing

pi lines

2 : capable of being inserted only by hand

pi characters

First Known Use of pi

circa 1940

in the meaning defined at sense 1

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PI

abbreviation

Definition of PI

1 Philippine Islands

2 private investigator

3 programmed instruction

See PI defined for English-language learners

PI Defined for Kids

pi

noun \ ˈpī \

Definition of pi for Students

plural pis \ˈpīz\

1 : the symbol π representing the ratio of the circumference of a circle to its diameter

2 : the ratio itself having a value of about 3.1416

Law Dictionary

P&I

abbreviation

legal Definition of P&I

principal and interest

PI

abbreviation

legal Definition of PI

private investigator

Learn More about pi

See words that rhyme with pi Spanish Central: Translation of pi Nglish: Translation of pi for Spanish speakers Britannica.com: Encyclopedia article about pi

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pi

Definition of pi

Origin and Etymology of pi

Other Alphabet Terms

pi

Definition of pi

Origin and Etymology of pi

pi

Definition of pi

First Known Use of pi

pi

Definition of pi

First Known Use of pi

PI

Definition of PI

Phrases Related to PI

Related Phrases

PI Defined for Kids

pi

Definition of pi for Students

Law Dictionary

P&I

legal Definition of P&I

PI

legal Definition of PI

Learn More about pi

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