**Pi** (?), n. [See Pica, Pie magpie, service-book.] (Print.)

A mass of type confusedly mixed or unsorted. [Written also *pie*.]

© Webster 1913

**Pi**, v. t. [imp. & p. p. Pied (?); p. pr. & vb. n. Pieing (?).] (Print.)

To put into a mixed and disordered condition, as type; to mix and disarrange the type of; as, to *pi* a form. [Written also *pie*.]

© Webster 1913

**Pi** (pI), n. [Gr. *pi^*.]

**1.**

A Greek letter (Π, π) corresponding to the Roman letter P.

**2.**

Specif.: (Math.) The letter Π, π, 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 eight decimal places, is 3.14159265. The quotient *pi* cannot be expressed as a root of an algebraic equation; 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.

© Webster 1913