Definition of pi
pis
play \ˈpīz\1 : the 16th letter of the Greek alphabet — see alphabet table
2a : the symbol π denoting the ratio of the circumference of a circle to its diameterb : the ratio itself : a transcendental number having a value rounded to eight decimal places of 3.14159265
Origin and Etymology of pi
Middle Greek, from Greek pei, of Semitic origin; akin to Hebrew pē pe
First Known Use: 15th century
Origin and Etymology of pi
origin unknown
First Known Use: circa 1659
pi
pie
Definition of pi
pied
;piing
orpieing
transitive verb
: to spill or throw (type or type matter) into disorder
intransitive verb
: to become pied
1889
First Known Use of pi
1889
pi
pie
Definition of pi
1 : not intended to appear in final printing pi lines
2 : capable of being inserted only by hand pi characters
Circa 1940
First Known Use of pi
circa 1940
PI
Definition of PI
1 Philippine Islands
2 private investigator
3 programmed instruction
PI Defined for Kids
pi
playDefinition of pi for Students
pis
\ˈpīz\1 : the symbol π representing the ratio of the circumference of a circle to its diameter
2 : the ratio itself having a value of about 3.1416
Law Dictionary
PI
Legal Definition of PI
private investigator
Learn More about pi

See words that rhyme with pi Spanish Central: Translation of pi Nglish: Translation of pi for Spanish speakers Britannica.com: Encyclopedia article about pi
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