envelope

From French enveloppe. The engineering sense is derived from flight envelope. The verb is from the noun.^[1]

• (Received Pronunciation) IPA^(key): /ˈɛnvələʊp/, /ˈɒnvələʊp/, (chiefly a wrapping) /ˈɒnvləʊp/, (dated) /ˈɑ̃vələʊp/

• Audio (Received Pronunciation):

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  Audio:

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• (General American) enPR: ĕn′vəlōp', än′vəlōp', IPA^(key): /ˈɛnvəˌloʊp/, /ˈɑn-/, /-lop/

• Audio (General American):

  (file)

  Audio:

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• Hyphenation: en‧vel‧ope

envelope (plural envelopes)

1. A paper or cardboard wrapper used to enclose small, flat items, especially letters, for mailing.
   • 2013 June 14, Jonathan Freedland, “Obama's once hip brand is now tainted”, in The Guardian Weekly, volume 189, number 1, page 18:

     Now we are liberal with our innermost secrets, spraying them into the public ether with a generosity our forebears could not have imagined. Where we once sent love letters in a sealed envelope, or stuck photographs of our children in a family album, now such private material is despatched to servers and clouds operated by people we don't know and will never meet.

2. Something that envelops; a wrapping.

   Synonym: wrapper

3. A bag containing the lifting gas of a balloon or airship; fabric that encloses the gas-bags of an airship.

   Synonym: gasbag

   • 1992, Lieutenant Colonel Donald E. Ryan, Jr, The airship's potential for intertheater and intratheater airlift, DIANE Publishing, page 46:

     They have no internal or external support structure, being simply a fabric bag (or envelope) filled with a lighter than air gas. Inside the envelope are one or more "ballonets", or smaller bags, which help maintain the envelope's shape.

4. (geometry) A mathematical curve, surface, or higher-dimensional object that is the tangent to a given family of lines, curves, surfaces, or higher-dimensional objects.
5. (electronics) A curve that bounds another curve or set of curves, as the modulation envelope of an amplitude-modulated carrier wave in electronics.
6. (music) The shape of a sound, which may be controlled by a synthesizer or sampler.
7. (networking) The information used for routing a message that is transmitted with the message but not part of its contents.

   Synonym: header

8. (biology) An enclosing structure or cover, such as a membrane; a space between two membranes
9. (engineering) The set of limitations within which a technological system can perform safely and effectively.

   push the envelope

   • 1980, Tom Wolfe, The Right Stuff, Bantam Books, →ISBN, page 350:

     Few of the lads had ever been in combat and they knew little about the critical tolerances of fighter aircraft during violent maneuvers. They knew where the outside of the envelope was, but they didn't know about the part where you reached the outside and then stretched her a little . . .

10. (astronomy) The nebulous covering of the head or nucleus of a comet; a coma.
11. An earthwork in the form of a single parapet or a small rampart, sometimes raised in the ditch and sometimes beyond it.
    • 1816, James Stanier Clarke, The Life of James the Second King of England:

      make a blind all along the bottom of the ditch of the Envelope

envelope (third-person singular simple present envelopes, present participle enveloping, simple past and past participle enveloped)

1. (transitive, rare) To put (something) in an envelope.^[1]
   • 1836, [Catherine Gore], chapter VII, in Mrs. Armytage; or, Female Domination. […], volume II, London: Henry Colburn, […], page 109:

     Arthur Armytage drew the precious document from his bureau; and without trusting himself to a re-perusal, enveloped and re-enveloped—sealed and resealed it;—mounted his horse, and rode off to Greta Castle.

   • 1873 November 8, Louis Bagger, “The Dead-Letter Office”, in Appletons’ Journal, volume X, number 242, New York, N.Y., page 595, column 1:

     This business of returning letters to the writers gives occupation to about sixty lady clerks in the “Return-Letter Department,” in the gallery up-stairs. To them belong the duties of reënveloping the letters in the well-known, yellow, dead-letter envelope, by which, under an act of Congress approved June 12, 1866, these are returned to the writers free of charge.

   • 1857 July 3, Augustus de Morgan, “[Correspondence between Sir William Rowan Hamilton and Professor Augustus De Morgan.] From A. De Morgan to Sir W. R. Hamilton.”, in Robert Perceval Graves, Life of Sir William Rowan Hamilton, […]: Including Selections from His Poems, Correspondence, and Miscellaneous Writings (Dublin University Press Series), volume III, Dublin: Hodges, Figgis, & Co., […]; London: Longmans, Green, & Co., […], published 1889, page 519:

     I suspect you write letters as hens lay eggs, find that Lady Hamilton finds them, envelopes them, puts them before you as official letters, and you direct them as per memorandum affixed.

   • 1919, William De Morgan, chapter XX, in The Old Madhouse, Toronto, Ont.: J[oseph] M[alaby] Dent and Sons, Ltd., page 308:

     It—the letter—was only an expression of the sender’s ardent desire to lend him, if not a minor, ten thousand pounds on his own security in the strictest confidence. To play his part out, he re-enveloped and pocketed it.

   • 1993 February 25, Don Lander, “Curing Canadians of mail mania”, in The Ottawa Citizen, Ottawa, Ont., published 1993 March 1, page A8:

     Successes such as these have paved the way for our most recent marketing innovation. I refer to Canada Post edict No. 58291, stating that we will no longer redirect first-class mail without charge when households move. Ordering the new householder to re-envelope the mail and pay another 43 cents was a stroke of genius. New revenue potential is substantial — nearly 400,000 Canadians move to another province in any year and far more move within their province.

   • 2003 December 22, “Sister's return of post anguish”, in Evening Chronicle‎^[1], Newcastle upon Tyne, archived from the original on 15 January 2024:

     It seems Royal Mail read Mrs Gowan's address label on the back of the envelopes, instead of the handwritten addresses on the front. / Desperate to get them to their intended destination before Christmas, Mrs Gowans re-enveloped the cards, bought new stamps and airmail stickers and sent them on their way, again.

• Wikipedia article on envelopes used for mailing
• Wikipedia article on envelopes in geometry
• ✉

See envelop.

• enPR: ĕn-vĕl'əp, IPA^(key): /ɛnˈvɛləp/
• for audio, see envelop

envelope (third-person singular simple present envelopes, present participle enveloping, simple past and past participle enveloped)

1. Archaic form of envelop.
   • 1877, James Booth, A Treatise on Some New Geometrical Methods, page 209:

     Again, if the plane of the impressed couple intersects the mean plane between N and C, it will envelope the cone whose focals are ON, ON′, and whose internal axis is therefore OA.

 envelope on Portuguese Wikipedia

Borrowed from French enveloppe, from envelopper.

• Hyphenation: en‧ve‧lo‧pe

envelope m (plural envelopes)

1. envelope

envelope

1. inflection of envelopar:
   1. first/third-person singular present subjunctive
   2. third-person singular imperative

• “envelope”, in Dicionário Priberam da Língua Portuguesa (in Portuguese), Lisbon: Priberam, 2008–2024