1

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 pe

Other Alphabet Terms


2

pi

noun \ ˈpī \
variants: or less commonly

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


3

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


4

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


PI

abbreviation

Definition of PI

1 Philippine Islands
2 private investigator
3 programmed instruction


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


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