envelope

[en-vuh-lohp, ahn-]

SEE MORE SYNONYMS FOR envelope ON THESAURUS.COM

noun

a flat paper container, as for a letter or thin package, usually having a gummed flap or other means of closure.

something that envelops; a wrapper, integument, or surrounding cover.

Biology. a surrounding or enclosing structure, as a corolla or an outer membrane.

Geometry. a curve or surface tangent to each member of a set of curves or surfaces.

Radio. (of a modulated carrier wave) a curve connecting the peaks of a graph of the instantaneous value of the electric or magnetic component of the carrier wave as a function of time.

the fabric structure enclosing the gasbag of an aerostat.

the gasbag itself.

Electronics. the airtight glass or metal housing of a vacuum tube.

the technical limits within which an aircraft or electronic system may be safely operated.

Idioms

push the envelope, to stretch established limits, as in technological advance or social innovation.

Also envelop.

Origin of envelope

1700–10; < French enveloppe, derivative of envelopper to envelop

Can be confusedenvelop envelope

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for envelope

box, jacket, casing, container, coat, pocket, bag, pouch, case, shell, hide, covering, cover, cloak, skin, vesicle, sheath, coating, receptacle, enclosure

Examples from the Web for envelope

Contemporary Examples of envelope

He started out with solo flights, but in this session over the desert outside Dubai he really pushes the envelope.
Daredevil in a Jetpack Flies Alongside A Plane
Jack Holmes, The Daily Beast Video
December 12, 2014
The parental fold may be about to envelope you—and yet also drive you mad.
How to Make It Through Thanksgiving Alive
Lizzie Crocker
November 26, 2014
On one occasion, Garrison said Williams had him hand one out-of-state doctor an envelope stuffed with $20,000 in cash.
Patients Screwed in Spine Surgery ‘Scam’
The Center for Investigative Reporting
November 3, 2014
The envelope also contains a warning about the federal penalties for obstructing the mail.
Grimes Campaign “Exploring Legal Options” Against McConnell
Ben Jacobs
October 31, 2014
Prince William was seen clutching an envelope, when they left, most likely containing images of the scan.
Royal Baby Due In April
Tom Sykes
October 20, 2014

Historical Examples of envelope

He took the card from the florist's envelope and glanced at the name.
The Spenders
Harry Leon Wilson
When she had gone he picked up an envelope and put a bill inside.
The Spenders
Harry Leon Wilson
"Because I want to do it myself," she said at last, and thrust the envelope into the flame.
K
Mary Roberts Rinehart
She drew it in pencil on an envelope on her way back in the street car.
K
Mary Roberts Rinehart
Before I open this envelope I am going to tell you what I believe it contains.
Her Father's Daughter
Gene Stratton-Porter

British Dictionary definitions for envelope

envelope

noun

a flat covering of paper, usually rectangular in shape and with a flap that can be folded over and sealed, used to enclose a letter, etc

any covering or wrapper

biology any enclosing structure, such as a membrane, shell, or skin

the bag enclosing the gas in a balloon

maths a curve or surface that is tangent to each one of a group of curves or surfaces

electronics the sealed glass or metal housing of a valve, electric light, etc

telecomm the outer shape of a modulated wave, formed by the peaks of successive cycles of the carrier wave

push the envelope informal to push the boundaries of what is possible

Word Origin for envelope

C18: from French enveloppe, from envelopper to wrap around; see envelop; sense 8 from aeronautics jargon, referring to graphs of aircraft performance

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for envelope

1705, from French enveloppe (13c.), a back-formation from envelopper "to envelop" (see envelop).

envelope in Medicine

envelope

[ĕn′və-lōp′, ŏn′-]

n.

An enclosing structure or cover, such as a membrane or the outer coat of a virus.