# DSI vs dup

> English confusable word pair

## The two words

### DSI
*noun · IPA /diː ɛs aɪ/ · frequency rank #47,027*
Initialism of diffused surface illumination.

### dup
*verb · IPA /dʌp/ · frequency rank #28,177*
to open (a door, gate etc.)

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/vs/dsi-vs-dup