pi

noun (1)

\ ˈpī

plural pis\ ˈpīz

Definition of pi

(Entry 1 of 5)

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

2a : 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

noun (2)

\ ˈpī

variants: or less commonly pie

plural pies

Definition of pi (Entry 2 of 5)

1 : type that is spilled or mixed

2 : a pi character or matrix

verb

variants: or less commonly pie

pied; piing or pieing

Definition of pi (Entry 3 of 5)

transitive verb

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

intransitive verb

: to become pied

adjective

variants: or less commonly pie

Definition of pi (Entry 4 of 5)

1 : not intended to appear in final printing pi lines

2 : capable of being inserted only by hand pi characters

abbreviation

Definition of PI (Entry 5 of 5)

1 Philippine Islands

2 private investigator

3 programmed instruction

First Known Use of pi

Noun (1)

15th century, in the meaning defined at sense 1

Noun (2)

circa 1659, in the meaning defined at sense 1

Verb

1889, in the meaning defined at transitive sense

Adjective

circa 1940, in the meaning defined at sense 1

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More Definitions for pi

noun

\ ˈpī

plural pis\ ˈpīz \

Kids Definition of pi

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

P&I

abbreviation

Legal Definition of P&I

(Entry 1 of 2)

principal and interest

abbreviation

Legal Definition of PI (Entry 2 of 2)

private investigator

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pi

Definition of pi

First Known Use of pi

History and Etymology for pi

Learn More about pi

Dictionary Entries near pi

Statistics for pi

The first known use of pi was in the 15th century

Kids Definition of pi