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breach (brēch)
a. An opening, tear, or rupture.
b. A gap or rift, especially in a solid structure such as a dike or fortification.
2. A violation or infraction, as of a contract, law, legal obligation, or promise.
3. A breaking up or disruption of friendly relations; an estrangement.
4. A leap of a whale from the water.
5. The breaking of waves or surf.
v. breached, breach·ing, breach·es
1. To make a hole or gap in; break through.
2. To break or violate (an agreement, for example).
1. To leap from the water: waiting for the whale to breach.
2. To develop a hole or opening. Used especially of protective embankments: The rising river caused the levee to breach.

[Middle English breche, from Old English brēc; see bhreg- in the Appendix of Indo-European roots.]

Synonyms: breach, infraction, violation, transgression, trespass, infringement
These nouns denote an act or instance of breaking a law or regulation or of failing to fulfill a duty, obligation, or promise. Breach and infraction are the least specific; when applied to lawbreaking they may imply a relatively minor offense, but they are also widely used in nonlegal contexts: Revealing the secret would be a breach of trust. Their behavior amounted to an infraction of the unwritten social code. Violation generally applies to the breaking of an explicit law or rule (a traffic violation; a violation of international law); it can also imply a failing to follow a moral or ethical standard: a violation of human rights; a violation of one's privacy. Transgression and trespass most often apply to divine or moral law: "She had said that the transgression was all the more shocking because the official was charged with enforcing federal laws against sexual harassment" (Jane Mayer and Jill Abramson). "The act of torture is such an extreme trespass against the laws of war that it may seem beside the point to wonder whether any other forms of wrongdoing have been carried out" (Elaine Scarry).
Infringement is most frequently used to denote encroachment on another's rights: "Necessity is the plea for every infringement of human freedom" (William Pitt the Younger).
(click for a larger image)
humpback whale breaching

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.