PI
|PI|
/paɪ/
circle ratio
Etymology
'PI' originates from the Greek letter 'π', which is the first letter of the Greek word 'periphery' (περίμετρος), meaning 'circumference'.
The symbol 'π' was first used to represent the mathematical constant by Welsh mathematician William Jones in 1706, and it was later popularized by Swiss mathematician Leonhard Euler.
Initially, 'π' was used to denote the ratio of a circle's circumference to its diameter, and this meaning has remained consistent in modern usage.
Meanings by Part of Speech
Noun 1
the mathematical constant representing the ratio of a circle's circumference to its diameter, approximately equal to 3.14159.
The value of PI is crucial in geometry and trigonometry.
Noun 2
a private investigator, often hired to conduct investigations.
She hired a PI to find out more about her business partner.
Synonyms
Last updated: 2025/03/07 16:06