[p_ˈaɪ], [pˈa͡ɪ], [pˈaɪ]
Definitions of pi

the ratio of the circumference to the diameter of a circle

the 16th letter of the Greek alphabet

Specif.: ( Math.) The letter /, /, 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.

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.

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

Specif.: ( Math.) The letter , 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.

Jumbled printing type.

To jumble, as type. Also, pie.

Print. Type that has been thrown into disorder.
Usage examples for pi

The cavalcade was increased during the afternoon by the addition to our numbers of a dog a distinctly ugly, red haired native sort of dog, commonly called a pi dog. – A Holiday in the Happy Valley with Pen and Pencil by T. R. Swinburne

" I wonder Chip pi ti chip doesn't get tired of that song," said Dot. – Dot and the Kangaroo by Ethel C. Pedley

Because, to find the area of the surface of a sphere we multiply the square of the diameter by pi; to find the volume of a sphere we multiply the cube of the diameter by one sixth of pi. – Amusements in Mathematics by Henry Ernest Dudeney

Eu pi hate; Crow  pi hate. – The Dakotan Languages, and Their Relations to Other Languages by Andrew Woods Williamson

Upon the first or eastern mesa are located the three towns of Te wa, Si chom ovi and Wal pi. – Arizona Sketches by Joseph A. Munk

I thought it must have come from the bake shop where they do all the other pi. – The Dominant Strain by Anna Chapin Ray

They do say that he was talking to Miss Walker about one of the faculty pews, and he said: 'Do you occupew this pi? – Molly Brown's Sophomore Days by Nell Speed

I'm awaiting my next swishing for upsetting my cup at breakfast in your defence, so I hardly think I deserve any pi jaw from you, do I? – The Bars of Iron by Ethel May Dell

As he talked to himself, he thought he heard sounds of pipes and drums coming from a distance: pi pi pi, pi pi pi. – The Adventures of Pinocchio by C. CollodiPseudonym of Carlo Lorenzini

Certainly it was a very tough duck, but still, I do not think a pi dog should he so fastidious. – A Holiday in the Happy Valley with Pen and Pencil by T. R. Swinburne

As that was Sunday we spent the morning " pi rooting" about the place. – The Prairie Wife by Arthur Stringer

Well, we have been making this " pi" for a hundred years; it seems to be a national dish in considerable favor with the rest of the world even such ancient nations as China and Japan want a piece of it. – The Complete Essays of C. D. Warner by Charles Dudley Warner