What Does “Pi” Mean, And Where Does It Come From?
Pi is the Latin name of the sixteenth Greek letter, π. (Mathematic notation borrows from a multitude of alphabets and typefaces.) The first recorded use of π as a mathematical symbol comes from the Welsh mathematician William Jones in a 1706 work called Synopsis Palmariorum Matheseos, in which he abbreviated the Greek περιϕέρεια, (meaning “circumference,” or “periphery”) to its first letter: π.
What does pi mean in mathematics? The mathematical pi is defined as “the ratio of the circumference of a circle to its diameter.” It’s also known as Archimedes’ Constant, after the ancient Greek mathematician of the same name, who, in addition to coming up with an algorithm for calculating pi, also invented an early type of irrigation pump called the Archimedian screw. Very medieval-sounding, but we digress.
What makes pi so magical is that it doesn’t matter how big or small the circle may be: the pi ratio remains the same. Pi is what’s known as an irrational number, which means, in part, that “it can never terminate or repeat when written out in decimal form.” As far as we can tell, it goes on forever, which is a bit mind-boggling. Computers have calculated pi to decimal places in the trillions. It is also a transcendental number, a concept that exceeds the scope of this post but is interesting in and of itself.
