# pi; Π, π +

#### (Greek: the sixteenth letter of the Greek alphabet; Π, π)

pi (math value)

1. A mathematical value equaling the ratio of the circumference of a circle to its diameter, expressed as 3.1416 or 22/7.

2. A number approximately equal to 3.14159 (3.14159265) that is the ratio of the circumference of a circle to its diameter and is represented by the symbol π.

2. A number approximately equal to 3.14159 (3.14159265) that is the ratio of the circumference of a circle to its diameter and is represented by the symbol π.

For any circle, the constant irrational number that is the ratio of the circumference to the diameter; denoted by π.

pi (Greek letter)

1. The name of the sixteenth letter of the Greek alphabet (Π, π); represented in the English alphabet as "p".

2. As a numeral, it denotes 80.

2. As a numeral, it denotes 80.

pi attenuator

An attenuator consisting of a pi network whose impedances (oppositions to flows of alternating currents) are all resistances.

An attenuator is a device for reducing the strength of a wave, especially an electrical signal.

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