# pi

## English

 ← omicron → rho Π π Ancient Greek: πεῖ Wikipedia article on pi
This mosaic is outside the mathematics building at the Technische Universität Berlin.
When a circle's diameter is 1 unit, its circumference is π units.
When a circle's radius is 1 unit, its circumference is 2π units.

### Etymology

From Ancient Greek πεῖ (peî). Its mathematical use apparently stems from its use as the first letter in περιφέρεια (periféreia, periphery; circumference) and was first cited in 1706 in the Synopsis Palmariorum Matheseos by William Jones.

### Pronunciation

• IPA(key): /paɪ/
•  Audio (US) Sorry, your browser either has JavaScript disabled or does not have any supported player. You can download the clip or download a player to play the clip in your browser. (file)
• Rhymes: -aɪ
• Homophone: pie

### Noun

pi (plural pis)

1. The name of the sixteenth letter of the Classical and Modern Greek alphabets and the seventeenth in Old Greek.
2. (mathematics) An irrational and transcendental constant representing the ratio of the circumference of a Euclidean circle to its diameter; approximately 3.1415926535897932384626433832795; usually written π.
3. (letterpress typography) Metal type that has been spilled, mixed together, or disordered. Also called pie.

### Verb

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

1. (letterpress typography) To spill or mix printing type. Also, "to pie".

pi (not comparable)

1. (typography) Not part of the usual font character set; especially, non-Roman type or symbols as opposed to standard alphanumeric Roman type.
In computing, pi characters are entered with special combinations of keys like ctrl-alt-x, or via character sequences such as &#123;.

### Abbreviation

pi

1. (typography) pica (conventionally, 12 points = 1 pica, 6 picas = 1 inch)
2. piaster
3. pious
• 1927, Magdalen King-Hall, I Think I Remember: Being the Random Recollections of Sir Wickham Woolicomb, an Ordinary English Snob and Gentleman
Our Major was "Cherub" Cheeseman, noted for his foul language. I am afraid he lost a tidy little legacy that he was expecting from his aunt, the Dowager Lady Shuttlecock (a very "pi" old lady), through this same habit of his.
• 1972, Anya Seton, Green Darkness, Hachette UK (ISBN 9781444709155)
“Those are very 'pi' sentiments. Was a preacher in Staffordshire— I was raised chapel, though've tried to forget it—he talked that way... redemption and the lot.”
• 1994, Roger Gard, Jane Austen's Novels: The Art of Clarity, Yale University Press (ISBN 9780300059267), page 101
In Sense and Sensibility, as even you might agree, there's at least the danger of a rather pi moral framework clamping down on the spontaneous fun and leaving the sisters to survive - a bit drearily - on the periphery of a mean world.

## Albanian

### Etymology

From Proto-Albanian *pīja, from Proto-Indo-European *pih₃- (compare Greek πίνω (píno), Serbo-Croatian pìti, Italian bere).

### Verb

pi (first-person singular past tense piva, participle pirë)

1. I drink

#### Conjugation

This verb needs an inflection-table template.

#### Usage notes

• ai pi - he is a drinker
• nuk pi duhan - I do not smoke

## Aromanian

### Etymology

From Latin per. Compare Daco-Romanian pe.

pi

## Catalan

### Etymology 1

From Latin pinus.

#### Noun

pi m (plural pins)

1. pine; evergreen tree of the genus Pinus.
2. pinewood

### Etymology 2

#### Noun

pi f (plural pis)

1. Pi; the Greek letter Π (lowercase π).

## Dalmatian

### Etymology

From Latin pes, pedem.

### Noun

pi m (plural pič)

## French

### Etymology 1

#### Noun

pi m (plural pi)

1. pi (Greek letter)
2. (mathematics) pi

### Etymology 2

#### Conjunction

pi

1. (Quebec, colloquial) Alternative spelling of pis and.