PI

pi

(noun) the 16th letter of the Greek alphabet

pi

(noun) the ratio of the circumference to the diameter of a circle; approximately equal to 3.14159265358979323846...

Source: WordNet® 3.1

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Etymology 1

Noun

pi (countable and uncountable, plural pis)

The 16th letter of the Classical and Modern Greek alphabets and the seventeenth in Old Greek.

(mathematics) An irrational and transcendental constant representing the ratio of the circumference of a Euclidean circle to its diameter; approximately 3.14159265358979323846264338327950; usually written π.

(metal typesetting) Metal type that has been spilled, mixed together, or disordered.

Synonym: pie

Synonyms

• (irrational constant): Archimedes' constant, Ludolphian number, Ludolph's constant, Ludolph's number

Verb

pi (third-person singular simple present pies, present participle piing, simple past and past participle pied)

(metal typesetting) To spill or mix printing type.

Synonym: pie

Adjective

pi (not comparable)

(typography) Not part of the usual font character set; especially, non-Roman type or symbols as opposed to standard alphanumeric Roman type.

Etymology 2

Abbreviations

Noun

pi

(typography) pica (conventionally, 12 points = 1 pica, 6 picas ≈ 1 inch)

piaster

Adjective

pi

pious

Anagrams

• IP, Ip

Etymology

Proper noun

Pi

(historical) A county of Chengdu, Sichuan, China.

Synonyms

• Pixian; Pe Heen, P'i Hsien (obsolete)

Anagrams

• IP, Ip

Proper noun

PI

Abbreviation of Piauí, a state of Brazil.

Initialism of Prison Industries (the prison-run work program for inmates)

(colloquial, Philippines) Initialism of Philippine Islands.

Noun

PI (countable and uncountable, plural PIs)

(informatics, SGML, XML) Initialism of processing instruction.

Initialism of partial induction (see AI)

Initialism of personal injury.

Initialism of politically incorrect (see PC)

Initialism of principal investigator (lead researcher on a grant-funded project)

Initialism of private investigator.

(biochemistry) Abbreviation of phosphatidylinositol (a phospholipid component of eukaryotic cell membranes, also abbreviated in PtdIns)

(pharmaceutical drug) Initialism of protease inhibitor.

(organic compound) Initialism of polyimide.

(medicine) Initialism of ponderal index.

(electronics) Initialism of power integrity.

Abbreviation of prohibited immigrant.

(fan fiction category) Initialism of pseudoincest.

(automotive) Initialism of port injection. (fuel injection)

Anagrams

• IP, Ip

Source: Wiktionary

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