Pi definition

An irrational number that has a numerical value of 3.14159265358979... and is represented by the symbol π. It expresses the ratio of the circumference to the diameter of a circle and appears in many mathematical expressions.
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Any jumble or mixture.
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The sixteenth letter of the Greek alphabet (Π, π)
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Private investigator.
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The 16th letter of the Greek alphabet. It is used as a symbol for the ratio of the circumference of a circle to its diameter, which is 3.141592653, commonly rounded to 3.14. Perhaps no other number has been more pondered, examined and calculated than pi. Circa 1650 B.C., the ratio was computed by an Egyptian scribe, and the number was recorded as 3.16049 in the Rhind Papyrus. The writings described how to create a square area the same size as a circle.The Exact Value of PiOver the years, pi, which was named some 3,000 years later, has been calculated numerous times to the maximum decimal place that humans and calculating devices could take it. In 1596, it was calculated to 32 decimal places and up to 127 places by 1719. In 1949, the ENIAC took 70 hours to yield 2,037 digits. However, in 1997, a Hitachi mainframe computed pi to 51.5 billion digits in 29 hours. The bottom line is that the absolutely exact value of pi cannot be computed.
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The symbol (π) designating the ratio of the circumference of a circle to its diameter.
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The ratio itself, equal to 3.14159265+: often approximated as227
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Pi is the 16th letter of the Greek alphabet, or the numerical value of the ratio of the circumference of a circle to its diameter.

Π is the symbol for Pi in the Greek alphabet.

3.1415 is an example of Pi.

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The 16th letter of the Greek alphabet.
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(mathematics) A transcendental number, approximately 3.14159, represented by the symbol π, that expresses the ratio of the circumference to the diameter of a circle and appears as a constant in many mathematical expressions.
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To become jumbled.
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An amount of type that has been jumbled or thrown together at random.
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To jumble or mix up (type).
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Private investigator.
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A mixed, disordered collection of printing type.
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To make jumbled; mix up (type)
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The sixteenth letter of the Greek alphabet, is used to mathematically represent the ratio of the circumference of a circle to its diameter, which is equal to 3.14159265358979323846. . . . Pi is an infinite decimal, at least as far as we know. Pi has been calculated to many millions of decimal places, but to no end. Further, no repeating pattern has ever been discovered, and many mathematicians maintain that a repeating pattern is impossible. Pi has many important mathematical uses. For example, the area of a circle is pi times the square of the length of the radius, or A = r 2 , or pi r squared. Everyone, from middle school, knows that to be impossible, of course -- pies are round, some cakes are squared.
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Alternative Forms

Alternative Form of pi - p-i

Other Word Forms

Noun

Singular:
pi
Plural:
pis

Origin of pi

  • Late Greek from Greek pei of Phoenician origin p in Semitic roots

    From American Heritage Dictionary of the English Language, 5th Edition

  • Origin unknown

    From American Heritage Dictionary of the English Language, 5th Edition