# back-of-the-envelope

> English word · Adjective · IPA /ˌbæk‿əv ðiː ˈɛnvələʊp/

## Definitions
1. Especially of a calculation, estimation, or other reasoning, or an idea: approximate, rough, simplified.

## Etymology
A reference to a calculation or an idea that occurs to one being jotted down on an available scrap of paper, such as the back of an envelope.

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