envelope

American  

[en-vuh-lohp, ahn-] / ˈɛn vəˌloʊp, ˈɑn- /

noun

• envelopes
  plural

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

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

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

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

5. 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.

6. the fabric structure enclosing the gasbag of an aerostat.

7. the gasbag itself.

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

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

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idioms

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

envelope British  

/ ˈɛnvəˌləʊp, ˈɒn- /

noun

1. 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

2. any covering or wrapper

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

4. the bag enclosing the gas in a balloon

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

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

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

8. informal to push the boundaries of what is possible

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Other Word Forms

Noun Inflected Forms

• envelopes
  plural

Etymology

Origin of envelope

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

Explanation

An envelope is something that envelops, or wraps around. It usually refers to the thing you stick a stamp on and snail mail. In the early 1700s, envelope, the noun for "wrapper," evolved from the French enveloppe, meaning “to envelop.” Envelope is always a noun, unlike the verb envelop which means “to wrap, cloak.” Synonyms for envelope range from casing and enclosure to pouch and sheath. Virginia Woolf said, “Life is a luminous halo, a semi-transparent envelope surrounding us from the beginning.” She ditched hers by walking into a river with her pockets full of rocks.

Example Sentences

See Examples For:

envelope envelopes

Leaving the crunchy, ragged edges on the paper, we stuffed our notice of intent into an envelope.

From Salon ● Oct. 4, 2026

Ignacio grew up in East L.A., and showed esparza a big manila envelope stuffed with incredible sketches and drawings by Glugio “Gronk” Nicandro.

From Los Angeles Times ● Oct. 2, 2026

The number hidden in the envelope was the key that would finally unscramble his experimental data and reveal what his team had measured.

From Science Daily ● Sep. 20, 2026

The zeppelin design, which placed individual gas-filled containers within a rigidly framed outer envelope, was invented around the turn of the 20th century by Ferdinand von Zeppelin, a German aristocrat and general.

From The Wall Street Journal ● Sep. 18, 2026

My own face in graphite, sketched on the back of this envelope, half in profile as if the artist has just called my name.

From "The Brightwood Code" by Monica Hesse

Really, the questionable part of vertical dramas is the gambling-style structure that envelopes them, not some inherent problem with the content itself.

From Slate ● Sep. 26, 2026

When my recent stationery order arrived with a half-dozen additional printed cards and envelopes.

From The Wall Street Journal ● Sep. 23, 2026

Others said they didn’t have the time to redesign their ballot envelopes.

From Salon ● Sep. 15, 2026

Otherwise, you might be wondering what all the fuss is about when the envelopes are opened.

From Los Angeles Times ● Sep. 9, 2026

I break off from them at full speed, weaving around strollers, shoving between couples, clutching the envelopes to my chest.

From "What If It's Us" by Becky Albertalli and Adam Silvera

Related Words

• bag
• box
• casing
• coat
• container
• jacket
• pocket
• pouch