1

pi

play
noun \ˈpī\

Definition of pi

plural

pis

play \ˈpīz\
  1. 1 :  the 16th letter of the Greek alphabet — see alphabet table

  2. 2a :  the symbol π denoting the ratio of the circumference of a circle to its diameterb :  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 pe


First Known Use: 15th century

Other Alphabet Terms


2

pi

play
noun \ˈpī\
variants: or less commonly

Definition of pi

plural

pies

  1. 1 :  type that is spilled or mixed

  2. 2 :  a pi character or matrix

Origin and Etymology of pi

origin unknown


First Known Use: circa 1659


3

pi

verb
variants: or less commonly

Definition of pi

pied

;

piing

or

pieing

  1. transitive verb
  2. :  to spill or throw (type or type matter) into disorder

  3. intransitive verb
  4. :  to become pied

1889

First Known Use of pi

1889


4

pi

adjective
variants: or less commonly

Definition of pi

  1. 1 :  not intended to appear in final printing pi lines

  2. 2 :  capable of being inserted only by hand pi characters

Circa 1940

First Known Use of pi

circa 1940


PI

abbreviation

Definition of PI

  1. 1 Philippine Islands

  2. 2 private investigator

  3. 3 programmed instruction



PI Defined for Kids

pi

play
noun \ˈpī\

Definition of pi for Students

plural

pis

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

  2. 2 :  the ratio itself having a value of about 3.1416


Law Dictionary

PI

abbreviation

Legal Definition of PI

  1. private investigator



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