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law (lô)
1. A rule of conduct or procedure established by custom, agreement, or authority.
a. The body of rules and principles governing the affairs of a community and enforced by a political authority; a legal system: international law.
b. The condition of social order and justice created by adherence to such a system: a breakdown of law and civilized behavior.
3. A set of rules or principles dealing with a specific area of a legal system: tax law; criminal law.
a. A statute, ordinance, or other rule enacted by a legislature.
b. A judicially established legal requirement; a precedent.
a. The system of judicial administration giving effect to the laws of a community: All citizens are equal before the law.
b. Legal action or proceedings; litigation: submit a dispute to law.
c. An impromptu or extralegal system of justice substituted for established judicial procedure: frontier law.
a. An agency or agent responsible for enforcing the law. Often used with the: "The law ... stormed out of the woods as the vessel was being relieved of her cargo" (Sid Moody).
b. Informal A police officer. Often used with the.
a. The science and study of law; jurisprudence.
b. Knowledge of law.
c. The profession of an attorney.
8. Something, such as an order or a dictum, having absolute or unquestioned authority: The commander's word was law.
9. Law
a. A body of principles or precepts held to express the divine will, especially as revealed in the Bible.
b. The first five books of the Hebrew Scriptures.
10. A code of principles based on morality, conscience, or nature.
a. A rule or custom generally established in a particular domain: the unwritten laws of good sportsmanship.
b. A way of life: the law of the jungle.
a. A statement describing a relationship observed to be invariable between or among phenomena for all cases in which the specified conditions are met: the law of gravity.
b. A generalization based on consistent experience or results: the law of supply and demand.
13. Mathematics A general principle or rule that is assumed or that has been proven to hold between expressions.
14. A principle of organization, procedure, or technique: the laws of grammar; the laws of visual perspective.
a law unto (oneself)
A totally independent operator: An executive who is a law unto herself.
take the law into (one's) own hands
To mete out justice as one sees fit without due recourse to law enforcement agencies or the courts.

[Middle English, from Old English lagu, from Old Norse *lagu, variant of lag, that which is laid down; see legh- in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Law, John 1671-1729.
Scottish financier active in France, where he engaged in highly profitable speculation on the development of Louisiana. The investment scheme ultimately collapsed, and he fled the country in ruin (1720).

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Law, (Andrew) Bonar 1858-1923.
Canadian-born British politician who served as chancellor of the exchequer (1916-1919) and prime minister (1922-1923).

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.