Back-of-the-envelope

/ˌbæk‿əv ðiː ˈɛnvələʊp/ · adjective

Meaning

(idiomatic, informal) Especially of a calculation, estimation, or other reasoning, or an idea: approximate, rough, simplified..

Example Sentences

We can do some back-of-the-envelope calculations before all the facts come in.

[T]he original estimates are frequently back-of-the-envelope-type estimates made internally without detailed engineering studies, if you go all the way back to Day 1.

We joke about having to make back-of-the-envelope calculations, while in the university environment we might spend 2 or 3 weeks computerizing the calculations. I might say, however, that making back-of-the-envelope calculations and later checking them out on computers has impressed me that we have developed a considerable skill in back-of-the-envelope calculations.

On one defense item, somebody kept referring to it as a back-of-an-envelope cost estimate. Do you have a back-of-an-envelope cost estimate?

Apart from those manuscripts which were intended as more or less complete, self-contained works, [William] Petty left a huge body of papers, much of which amounts to fragments and hastily written private notes – many the seventeenth-century equipvament of back-of-the-envelope calculations and comments. These papers constitute a further testament to his sustained investigation of economic and political subjects.

The reader will not need to be warned that the calculations involved are of the back of an envelope type and statements of the form ‘a equals b’ should be read ‘a equals b approximately’ or even ‘with a bit of luck, a and b will be of the same order of magnitude’.

Misapplying a basic feature of diffusion theory, [Werner] Heisenberg arrived at an impossibly high figure for a critical mass of pure U235. This was done by means of a seductively simple "back of an envelope" calculation in 1940, […]

Back of the envelope calculation: I've traveled roughly 17 million miles since we left the crew quarters at Cape Kennedy, not including the van ride to the pad … in fact, Earth seems a bit dreamlike these days, as we are connected only by crackling voices on the radio and the photographs brought along and our memories.

Synonyms for back-of-the-envelope

Antonyms for back-of-the-envelope

Related Words

Word Forms

• back-of-an-envelope

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