use-icon

HOW TO USE THE DICTIONARY

To look up an entry in The American Heritage Dictionary of the English Language, use the search window above. For best results, after typing in the word, click on the “Search” button instead of using the “enter” key.

Some compound words (like bus rapid transit, dog whistle, or identity theft) don’t appear on the drop-down list when you type them in the search bar. For best results with compound words, place a quotation mark before the compound word in the search window.

guide to the dictionary

use-icon

THE USAGE PANEL

The Usage Panel is a group of nearly 200 prominent scholars, creative writers, journalists, diplomats, and others in occupations requiring mastery of language. Annual surveys have gauged the acceptability of particular usages and grammatical constructions.

The Panelists

puzzle-icon

NEED HELP SOLVING A CROSSWORD PUZZLE?

Go to our Crossword Puzzle Solver and type in the letters that you know, and the Solver will produce a list of possible solutions.

open-icon

AMERICAN HERITAGE DICTIONARY APP

The new American Heritage Dictionary app is now available for iOS and Android.

scroll-icon

THE AMERICAN HERITAGE DICTIONARY BLOG

The articles in our blog examine new words, revised definitions, interesting images from the fifth edition, discussions of usage, and more.

100-words-icon

See word lists from the best-selling 100 Words Series!

Find out more!

open-icon

INTERESTED IN DICTIONARIES?

Check out the Dictionary Society of North America at http://www.dictionarysociety.com

en·ve·lope (ĕnvə-lōp, ŏn-)
Share:
n.
1. A flat paper container, especially for a letter, usually having a gummed flap.
2. Something that envelops; a wrapping.
3. Biology An enclosing structure or cover, such as a membrane or the outer coat of a virus.
4. The bag containing the gas in a balloon or airship.
5. The set of limitations within which a technological system, especially an aircraft, can perform safely and effectively.
6. Astronomy
a. A usually spherical region of interstellar matter surrounding a forming star and interacting with the star's gravitational and radiation fields.
b. The coma of a comet.
7. Mathematics A curve or surface that is tangent to every one of a family of curves or surfaces.
Idiom:
push the envelope
To exceed or try to exceed the existing limits of a discipline or activity.

[French enveloppe, from envelopper, to envelop, from Old French envoloper; see ENVELOP.]

Usage Note: Some people dislike the pronunciation (ŏnvə-lōp), arguing that it is pretentious for being pseudo-French and that it is unnecessary, since there is a perfectly acceptable Anglicized pronunciation, (ĕnvə-lōp). But the pronunciation with (ŏn) is gaining in acceptability: in our 1992 survey, 30 percent of the Usage Panel used it exclusively, and another 9 percent used it occasionally; by 2011, 46 percent selected it as their preferred pronunciation. Both forms should be considered standard.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

This website is best viewed in Chrome, Firefox, Microsoft Edge, or Safari. Some characters in pronunciations and etymologies cannot be displayed properly in Internet Explorer.