Where does “пи” come from?

пи (Russian) comes from English pee, from English piss, from Middle English pisse, from Middle English pissen, from Old French pissier, from Vulgar Latin pissiare, from Latin pissio — I piss.

пи (Russian): P, p; Π, π; A mathematical constant pi

Definitions

  1. P, p; Π, π; A mathematical constant pi

Ancestry of “пи”, step by step

пи traces back through two separate lines of ancestry.

via English pee

StepLanguageWordMeaning
1EnglishpeeUrine; To urinate; To drizzle
2EnglishpissUrine; An instance of pissing; Alcoholic...
3Middle Englishpissepiss, urine; Alternative form of pissen
4Middle EnglishpissenTo piss; to deliver urine from the genitals; To...
5Old Frenchpissierto piss; to excrete urine
6Vulgar Latinpissiarepresent active infinitive of *pīssiō
7LatinpissioI piss

via Ancient Greek πεῖ

StepLanguageWordMeaning
1Ancient Greekπεῖpi, the name for the sixteenth letter Π, π of the...
2Proto-Semiticpay-the mouth
Every word from Latin pissio