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

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

closed (klōzd)
Share:
adj.
1. Having boundaries; enclosed: a closed corridor between the two buildings.
2. Blocked or barred to passage or entry: a closed port.
3. Explicitly limited; restricted: closed membership.
4. Self-contained or self-sufficient: a closed relationship.
5. Barred to the public; conducted in secrecy: a closed session of the judiciary committee.
6. Mathematics
a. Of or relating to a curve, such as a circle, having no endpoints.
b. Of or relating to a surface having no boundary curves.
c. Of or relating to an interval containing both its endpoints.
d. Characterized by or possessing the property by which an operation acting on an element in a set produces an element within the set.
7. Computers Of or relating to a file that cannot be accessed.
8. Electricity Allowing electricity to flow or pass: a closed switch.
9. Linguistics Ending in a consonant: a closed syllable.
10. Sports
a. Having the forward foot closer to the intended point of impact with the ball than the rear foot: a closed batting stance.
b. Held or swung with the top or outer edge of the striking face pointing slightly closer to the objective than the lower or inner edge: The club face was closed when it hit the ball, causing a hook.
11. Physics
a. Of or relating to a closed system.
b. Of or relating to a closed universe.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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.