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

mit·i·gate (mĭtĭ-gāt)
Share:
tr.v. mit·i·gat·ed, mit·i·gat·ing, mit·i·gates
1. To make less severe or intense; moderate or alleviate. See Synonyms at relieve.
2. To make alterations to (land) to make it less polluted or more hospitable to wildlife.
Phrasal Verb:
mitigate against Usage Problem
1. To take measures to moderate or alleviate (something).
2. To be a strong factor against (someone or something); hinder or prevent.

[Middle English mitigaten, from Latin mītigāre, mītigāt- : mītis, soft + agere, to drive, do; see ACT.]

miti·ga·ble (-gə-bəl) adj.
miti·gation n.
miti·gative, miti·ga·tory (-gə-tôrē) adj.
miti·gator n.

Usage Note: Mitigate, meaning "to make less severe, alleviate" is sometimes used where militate, which means "to cause a change," might be expected. The confusion arises when the subject of mitigate is an impersonal factor or influence, and the verb is followed by the preposition against, so the meaning of the phrase is something like "to be a powerful factor against" or "to hinder or prevent," as in His relative youth might mitigate against him in a national election. Some 70 percent of the Usage Panel rejected this usage of mitigate against in our 2009 survey. Some 56 percent also rejected the intransitive use of mitigate meaning "to take action to alleviate something undesirable," in What steps can the town take to mitigate against damage from coastal storms? Perhaps the use with against in the one instance has soured Panelists on its use in the other. This intransitive use is relatively recent in comparison with the long-established transitive use, so novelty might play a role as well.

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.