# unlesss

> English word · Conjunction

## Definitions
1. Precisely unless.

## Etymology
Attributed to John Horton Conway. From unless, by analogy with the formation of iff from if.

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