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moot (mt)
a. Subject to debate; arguable or unsettled: "It is a moot point whether Napoleon Bonaparte was born a subject of the King of France" (Norman Davies).
b. Of no practical importance; irrelevant: "[He] was appearing as a goodwill gesture, since the competition was moot for him; he had long ago qualified for inclusion in the games" (Mark Levine).
2. Law
a. Not presenting an open legal question, as a result of the occurrence of some event definitively resolving the issue, or the absence of a genuine case or controversy.
b. Of no legal significance; hypothetical.
tr.v. moot·ed, moot·ing, moots
a. To bring up (a subject) for discussion or debate. See Synonyms at broach1.
b. To discuss or debate: "The notion of eliminating the corporate income tax has been mooted in tax circles for years" (Francis X. Clines).
2. To render (a subject or issue) irrelevant: "The F.C.C.'s ability to regulate the broadcast media rested on the finite nature of the spectrum, and that has been mooted by the infinity of cable" (William Safire).
3. Law
a. To argue (a case) in a moot court.
b. To render (a legal issue or question) irrelevant.
1. Law
a. The discussion or argument of a hypothetical case by law students as an exercise.
b. A hypothetical case used for such a discussion or argument.
2. An ancient English meeting, especially a representative meeting of the freemen of a shire.

[Middle English, meeting, from Old English mōt, gemōt.]

mootness n.

Usage Note: The adjective moot is originally a legal term going back to the 1500s. It derives from the noun moot in its sense of a hypothetical case argued as an exercise by law students. The noun moot in turn goes back to an Old English word meaning "a meeting, especially one convened for legislative or judicial purposes." Consequently, a moot question is one that is arguable or open to debate. But in the mid-1800s, people also began to look at the hypothetical side of moot as its essential meaning, and they started to use the word to mean "of no significance or relevance." Thus a moot point, however debatable, is one that has no practical value. A number of critics have objected to this usage, but in our 2008 survey 83 percent of the Usage Panel accepted it in the sentence The nominee himself chastised the White House for failing to do more to support him, but his concerns became moot when a number of Republicans announced that they, too, would oppose the nomination. This represents a significant increase over the 59 percent that accepted the same sentence in 1988. Writers who use this word should be sure that the context makes clear which sense of moot is meant. It is often easier to use another word, such as debatable or irrelevant.

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.