# PCT vs pi

> English confusable word pair

## The two words

### PCT
*name · frequency rank #23,938*
Initialism of Patent Cooperation Treaty.

### pi
*noun · IPA /paɪ/ · frequency rank #8,073*
The sixteenth letter of the Classical and Modern Greek alphabets and the seventeenth in Old Greek.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-09-03.
Canonical page: https://plainspell.com/en/vs/pct-vs-pi