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# pi (n.)

Greek letter corresponding to the Roman P, from Phoenician, literally "little mouth." As the name of the mathematical constant for the ratio of the circumference of a circle to the diameter, from 1841 in English, used in Latin 1748 by Swiss mathematician Leonhard Euler (1707-1783), as an abbreviation of Greek periphereia "periphery." For the printer's term for mixed type (often spelled pi), see pie (3).

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Definitions of

*from WordNet**pi*### Dictionary entries near *pi*

physiotherapy

physique

-phyte

phyto-

phytoplankton

pi

pianissimo

pianist

piano

pianoforte

Pianola