Envelope Definition & Meaning

American

British

Etymology

Examples

Related Words

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

noun

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.

idioms

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

envelope British / ˈɒn-, ˈɛnvəˌləʊp /

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

"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

Etymology

Origin of envelope

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

It is painstaking, dismantling delicate gear assemblies, then searching hundreds of century-old envelopes for the tiny parts that will bring them back to life.

From The Wall Street Journal

The justice department on Tuesday called the letter a fake, noting several irregularities with the note and the envelope that held it.

From BBC

If you don’t have one readily available, you can also use small envelopes or cardboard boxes glued onto a piece of foam board.

From Salon

Her father had written the word "Liar" on the envelope.

From BBC

"Exosomes are like envelopes with important information," said Ibrahim, associate professor in the Department of Cardiology in the Smidt Heart Institute and first author of the paper.

From Science Daily

Related Words

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

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.