envelope

noun

en·​ve·​lope ˈen-və-ˌlōp  ˈän- 

1

: a flat usually paper container (as for a letter)

2

: something that envelops : wrapper

the envelope of air around the earth

3

a

: the outer covering of an aerostat

b

: the bag containing the gas in a balloon or airship

4

a

: a natural enclosing covering (such as a membrane, shell, or integument)

b

: a lipoprotein unit membrane that forms the outer layer of some virions

5

a

: a curve tangent to each of a family of curves

b

: a surface tangent to each of a family of surfaces

6

: a set of performance limits (as of an aircraft) that may not be safely exceeded

also : the set of operating parameters that exists within these limits

7

: a conventionally accepted limit

new computers that push the envelope

How do you pronounce envelope?: Usage Guide

The \ˈen-\ and \ˈän-\ pronunciations are used with about equal frequency, and both are fully acceptable, though the \ˈän-\ version is sometimes decried as "pseudo-French." Actually \ˈän-\ is exactly what one would expect to hear when a French word like entrepreneur is becoming anglicized. Envelope, however, has been in English for nearly 300 years, plenty of time for it to become completely anglicized and for both of its pronunciations to win respectability.

Examples of envelope in a Sentence

Recent Examples on the Web

In the 2020 election, election workers in Michigan's biggest cities could spend 10 hours the day before the election opening the absentee ballot return envelopes and check that the number on the stub attached to the ballot matched the number on the absentee ballot envelope. —Clara Hendrickson, Detroit Free Press, 5 Nov. 2024

In a separate case, Pennsylvania’s Supreme Court ruled that thousands of Pennsylvania mail-in ballots shouldn’t be counted if the date on the envelope wasn’t filled in correctly. —Brian Bennett, TIME, 5 Nov. 2024

Pennsylvania Supreme Court ruled mail-in ballots with an incorrect or missing date on the envelope can’t be counted, siding with Republicans after a lower court ruled that not counting those ballots in a separate special election violated the state Constitution. —Alison Durkee, Forbes, 4 Nov. 2024

No preprocessing of vote by mail or absentee ballots According to the Brennan Center for Justice, 43 states allow pre-processing of mail-in ballots, which includes verifying the voter’s information and eligibility on the mail ballot envelope, opening the envelope, and removing the ballot. —Erin Mansfield, USA TODAY, 3 Nov. 2024

Word History

First Known Use

circa 1714, in the meaning defined at sense 1

Phrases Containing envelope

• back-of-the-envelope
• floral envelope
• pay envelope
• push the envelope
• return envelope
• window envelope

Kids Definition

envelope

noun

en·​ve·​lope ˈen-və-ˌlōp  ˈän- 

1

: a flat usually paper container (as for a letter)

2

: something that envelops

3

: the bag containing the gas in a balloon or airship

4

: a natural enclosing covering (as a membrane)

Medical Definition

envelope

noun

en·​ve·​lope ˈen-və-ˌlōp  ˈän- 

: a natural enclosing covering (as a membrane or integument)

especially : a lipoprotein unit membrane that forms the outer layer of some virions and surrounds the viral capsid

These glycoprotein complexes, swept up by the budding virus as it acquires its envelope, are crucial to HIV's ability to infect new cells.

—William A. Haseltine et al., Scientific American