envelope
noun
en·ve·lope
ˈen-və-ˌlōp 
ˈän-
ˈän-
1
: a flat usually paper container (as for a letter)
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
Red Wolf is intended to push well beyond those limits, allowing aircrews to operate outside enemy air-defense envelopes.
—
Kapil Kajal, Interesting Engineering, 29 Dec. 2025
Non-Essential Mail Digging through a giant pile of envelopes and ads to find those few important bills can be a nightmare, which is why Lichtenstein recommends sorting through and throwing out unnecessary pieces of mail as soon as your daily delivery arrives.
—Nishaa Sharma, The Spruce, 29 Dec. 2025
Investigators surmised the thieves were familiar with the envelopes the bank used to store large amounts of customers' cash.
—Logan Smith, CBS News, 28 Dec. 2025
Almost 35 years later, the fight that started before that single envelope fluttered into his cell is not over.
—Faith Karimi, CNN Money, 27 Dec. 2025
See All Example Sentences for envelope
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Kapil Kajal, Interesting Engineering, 29 Dec. 2025
Non-Essential Mail Digging through a giant pile of envelopes and ads to find those few important bills can be a nightmare, which is why Lichtenstein recommends sorting through and throwing out unnecessary pieces of mail as soon as your daily delivery arrives.
—Nishaa Sharma, The Spruce, 29 Dec. 2025
Investigators surmised the thieves were familiar with the envelopes the bank used to store large amounts of customers' cash.
—Logan Smith, CBS News, 28 Dec. 2025
Almost 35 years later, the fight that started before that single envelope fluttered into his cell is not over.
—Faith Karimi, CNN Money, 27 Dec. 2025
See All Example Sentences for envelope
Cite this Entry
“Envelope.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/envelope. Accessed 2 Jan. 2026.
Copy CitationKids Definition
envelope
noun
en·ve·lope
ˈen-və-ˌlōp
ˈän-
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-
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
William A. Haseltine et al., Scientific American Love words? Need even more definitions?
Merriam-Webster unabridged
Share