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

bul·wark (blwərk, -wôrk, bŭl-)
1. A wall or embankment raised as a defensive fortification; a rampart.
2. Something serving as a defense or safeguard: "We have seen the necessity of the Union, as our bulwark against foreign danger" (James Madison).
3. A breakwater.
4. often bulwarks The part of a ship's side that is above the upper deck.
tr.v. bul·warked, bul·wark·ing, bul·warks
1. To fortify with a wall, embankment, or rampart.
2. To provide defense or protection for: "the wetland that bulwarked the pond" (Edward Hoagland).

[Middle English bulwerk, from Middle Dutch bolwerk, from Middle High German bolwerc : bole, plank; see bhel-2 in the Appendix of Indo-European roots + werc, work (from Old High German; see werg- in the Appendix of Indo-European roots).]

Synonyms: bulwark, barricade, breastwork, earthwork, rampart, bastion, parapet
These nouns refer literally to structures used as a defense against attack. A bulwark is a strong defensive barrier, often an embankment or wall-like fortification, from which fire can be directed. A barricade is an improvised barrier meant to stop or slow an advancing threat. Breastwork denotes a low defensive wall, especially a temporary one hurriedly built. An earthwork is an embankment made of soil, and may include a trench or moat. A rampart, the main defensive structure around a guarded place, is permanent, high, and broad. A bastion is a projecting section of a fortification from which defenders have a wide range of view and fire. Parapet applies to any low fortification, typically a wall atop a rampart. Of these words bulwark, bastion, and rampart are the most frequently used to refer figuratively to something regarded as being a safeguard or a source of protection: "The only sure bulwark of continuing liberty is a government strong enough to protect the interests of the people, and a people strong enough ... to maintain its sovereign control over its government" (Franklin D. Roosevelt). "the University of Virginia, a school founded by Jefferson to be a bastion of free thought" (Garry Wills). "The sense of being a couple ... is the strongest rampart against the relentless threat of our divorce culture" (Judith S. Wallerstein).

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.