tri·​ad | \ ˈtrī-ˌad also -əd How to pronounce triad (audio) \

Definition of triad

1 : a union or group of three : trinity
2 : a chord of three tones consisting of a root with its third and fifth and constituting the harmonic basis of tonal music

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Other Words from triad

triadic \ trī-​ˈa-​dik How to pronounce triadic (audio) \ adjective
triadically \ trī-​ˈa-​di-​k(ə-​)lē How to pronounce triadically (audio) \ adverb

Did You Know?

The best-known type of triad is a type of musical chord consisting of three notes. A D-major triad is made up of the notes D, F-sharp, and A; an F-minor triad is made up of F, A-flat, and C; and so on. Major and minor triads form the basis of tonal music, and songs and other pieces usually end with a triadic harmony. In medicine, a triad is a set of three symptoms that go together. The Chinese criminal organizations called triads got their name from the triangular symbol that they used back when they began, centuries ago, as patriotic organizations. Today, with over 100,000 members, the triads operate in the U.S., Canada, and many other countries.

Examples of triad in a Sentence

a triad of candlesticks on the mantle

Recent Examples on the Web

The nuclear triad covers the three ways that the United States can launch nuclear weapons. Chris Cillizza, CNN, "How is Donald Trump preparing for the huge North Korea summit? He's not.," 7 June 2018 If that's truly the case, then what use is a triad? Kyle Mizokami, Popular Mechanics, "Does America Still Need the Nuclear Triad?," 23 Jan. 2019 The success of LeMay’s campaign resulted in widespread acceptance of the idea that each leg of the strategic triad had to be capable of defeating the Soviets. WSJ, "Fix Pentagon Policy Before Seeking New Funds," 1 Jan. 2019 People who score high on the dark triad typically engage in behaviors that most people would find obnoxious or immoral. Glenn Geher, WSJ, "The Dark Triad and the Evolution of Jerks," 6 Dec. 2018 Founding member Robin Bernstein was confirmed as ambassador to the Dominican Republic, and there's of course the triad of Mar-a-Lago-ians shaping policy at the VA. Chloe Foussianes, Town & Country, "A Mar-a-Lago Member, Handbag Designer Lana Marks, Is Donald Trump's Pick for Ambassador to South Africa," 16 Nov. 2018 More than any other arm of the triad, missile submarines deter war by ensuring a revenge attack is possible. Kyle Mizokami, Popular Mechanics, "The U.S. Navy's Next Missile Sub Is Called USS Columbia," 15 Dec. 2016 That same showrunner also wanted me to feature Chinese triads, have them use Japanese throwing stars, and get into a kung-fu fight with our (white) lead. Adele Lim, Glamour, "Crazy Rich Asians Is the Love Letter to My People I Never Had a Chance to Write," 17 Aug. 2018 And the land leg of the US nuclear triad, the Minuteman III ICBM, entered service in the 1960s. Sean Gallagher, Ars Technica, "Sitrep: The Air Force’s senior-citizen chopper may have to hold off retirement," 31 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'triad.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of triad

1546, in the meaning defined at sense 1

History and Etymology for triad

Latin triad-, trias, from Greek, from treis three

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Statistics for triad

Last Updated

7 May 2019

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Time Traveler for triad

The first known use of triad was in 1546

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More Definitions for triad



English Language Learners Definition of triad

: a group of three usually related people or things
: a secret Chinese criminal organization


tri·​ad | \ ˈtrī-ˌad How to pronounce triad (audio) \

Kids Definition of triad

: a chord made up usually of the first, third, and fifth notes of a scale


tri·​ad | \ ˈtrī-ˌad also -əd\

Medical Definition of triad

1 : a union or group of three a triad of symptoms
2 : a trivalent element, atom, or radical

Other Words from triad

triadic \ trī-​ˈad-​ik How to pronounce triadic (audio) \ adjective

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More from Merriam-Webster on triad

Rhyming Dictionary: Words that rhyme with triad

Thesaurus: All synonyms and antonyms for triad

Spanish Central: Translation of triad

Nglish: Translation of triad for Spanish Speakers

Britannica English: Translation of triad for Arabic Speakers Encyclopedia article about triad

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