# unsubstitutably

> English word · Adverb

## Definitions
1. Such that it cannot be substituted, or used as a replacement or alternative.

## Etymology
From unsubstitutable + -ly.

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