plural pis
ˈpīz 
1
: the 16th letter of the Greek alphabet see Alphabet Table
2
a
: the symbol π denoting the ratio of the circumference of a circle to its diameter
b
: the ratio itself : a transcendental number having a value rounded to eight decimal places of 3.14159265
variants
or less commonly pie
plural pies
1
: type that is spilled or mixed
2
: a pi character or matrix
variants
or less commonly pie
pied; piing or pieing
: to spill or throw (type or type matter) into disorder
: to become pied
variants
or less commonly pie
1
: not intended to appear in final printing
pi lines
2
: capable of being inserted only by hand
pi characters
1
Philippine Islands
2
private investigator
3
programmed instruction
Examples of pi in a Sentence
Recent Examples on the Web
Ronald J. Hansen, The Arizona Republic, 26 July 2024
In math terms, pi is the circumference (the distance around the outside of the circle) divided by the diameter (the distance edge-to-edge of a circle when measured through the center).
—Cathy Kozlowicz, Journal Sentinel, 6 June 2024
The decimal values of pi have no end and never repeat.
—Manon Bischoff, Scientific American, 24 Jan. 2024
All over the world, people honor pi in various ways.
—Defne Karabatur, Los Angeles Times, 14 Mar. 2024
See all Example Sentences for pi 
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Noun
The 314 Action Fund, a name intended to evoke the math formula for pi, added its backing to those seeking to elevate Kelly, who is an engineer and former astronaut.
—Ronald J. Hansen, The Arizona Republic, 26 July 2024
In math terms, pi is the circumference (the distance around the outside of the circle) divided by the diameter (the distance edge-to-edge of a circle when measured through the center).
—Cathy Kozlowicz, Journal Sentinel, 6 June 2024
The decimal values of pi have no end and never repeat.
—Manon Bischoff, Scientific American, 24 Jan. 2024
All over the world, people honor pi in various ways.
—Defne Karabatur, Los Angeles Times, 14 Mar. 2024
See all Example Sentences for pi
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Dictionary Entries Near pi
Cite this Entry
“Pi.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pi. Accessed 28 Nov. 2024.
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