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



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



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



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


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

Find out more!



Check out the Dictionary Society of North America at

while (wīl, hwīl)
1. A period of time: stay for a while; sang all the while. See Usage Note at awhile.
2. The time, effort, or trouble taken in doing something: The project wasn't worth my while.
1. As long as; during the time that: It was lovely while it lasted.
2. In spite of the fact that; although: While that guitar may look nice, it's not a very good instrument.
3. And on the contrary: The soles are leather, while the uppers are canvas.
tr.v. whiled, whil·ing, whiles
To spend (time) idly or pleasantly: while the hours away.

[Middle English, from Old English hwīl; see kweiə- in the Appendix of Indo-European roots.]

Usage Note: As a conjunction, while is used to indicate that two events are happening at the same time (While I was preparing the hamburger patties, she sliced the onions and tomatoes), but it can also be used to contrast two clauses in a nontemporal way (While the "h" is silent in the word "honest," it is pronounced in the word "hostile"). While has been used in this nontemporal sense for hundreds of years, and the latter sentence was judged acceptable by 75 percent of the Usage Panel in our 2012 survey. The Panel was somewhat less accepting, however, of this use of while in a sentence where it could potentially be misread as having a temporal meaning (31 percent disapproved of the sentence She said she wanted to go to a movie, while he proposed seeing a play). And 43 percent disapproved of a sentence in which the two contrasting clauses are explicitly not simultaneous: While the Tigers beat the Cubs last week, this week the Cubs beat the Tigers. To avoid ambiguity or an unintended suggestion of simultaneity, choose a different conjunction, such as although or whereas.

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.