Definitions for

**"Pi"**A Greek letter (PI, p) corresponding to the Roman letter P.

The letter p, PI, as used to denote the number or quotient approximately expressing the ratio of the circumference of a circle to its diameter; also, the quotient or the ratio itself. The value of the quotient pi, to twenty decimal places, is 3.14159265358979323846 (see note). The number pi is an irrational number, i.e. it cannot be expressed as the quotient of two integers. It is also a transcendental number, i.e. it cannot be expressed as a root of an algebraic equation with a finite number of terms; and from this fact follows the impossibility of the quadrature of the circle by purely algebraic processes, or by the aid of a ruler and compass.

the 16th letter of the Greek alphabet

Protease Inhibitor

an antiviral drug used against HIV; interrupts HIV replication by binding and blocking HIV protease; often used in combination with other drugs

Penitentiaire Inrichting

A mass of type confusedly mixed or unsorted.

To put into a mixed and disordered condition, as type; to mix and disarrange the type of; as, to pi a form.

The inorganic orthophoshate ion; -- a symbol used in biochemistry.

Preliminary Investigation

Principal Investigator

the scientist in charge of an experiment or research project

someone who can be employed as a detective to collect information

Participating Interest

Performance Improvement

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