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

All this is set against the backdrop of the Chinese triad in San Francisco. Jennifer Ouellette, Ars Technica, "Review: Fight scenes are the only bright spot in grim, joyless Wu Assassins," 19 Aug. 2019 In late July, an armed mob brutally attacked civilians at a train station, yet police did not arrive until 40 minutes later, fueling suspicions of collusion with the criminal triads. Mary Hui, Quartz, "Mired in anger and hatred, Hong Kong’s “radical” protesters are seeking a way forward," 14 Aug. 2019 Hinojosa joined recent high school graduates Denver Hammons, Meghan Barber and Aliya Ellis and high school junior Blake Long as world champion Double Dutch mixed triad winners. Kelly Wilkinson, Indianapolis Star, "From Indianapolis to Oslo to Berlin: Indy Air Bears jump to the world stage," 9 Aug. 2019 This time, though, the actor doesn't play a babyfaced cop but a San Francisco chef, Kai Jin, who has found himself at odds with a Chinatown triad. Peter Rubin, WIRED, "Wu Assassins Gives Netflix New Footing in Streaming's Battle Royale," 8 Aug. 2019 So the triad decides to kidnap every bald chef in Chinatown, which should obviously cue the apocalyptic battle of the bald chefs! Noah Berlatsky, The Verge, "Netflix’s Wu Assassins series lacks the Hong Kong cinema magic," 8 Aug. 2019 Last month, local gangs called triads beat up protesters and civilians at random in a mass transit station, shocking a city that’s used to being one of the safest in the world. Sabra Ayres, Los Angeles Times, "Amid protests, defiance against Kremlin and Beijing rises," 2 Aug. 2019 In a real-life example, a 2013 leadership struggle in one Hong Kong triad was accompanied by a string of violent incidents, with police responding by raiding businesses tied to the group. Isabella Steger, Quartzy, "Six films to watch to understand what’s happening in Hong Kong," 24 July 2019 The police — who failed to stop the mob, and initially made no arrests — have since detained 12 people in connection with the train station attacks, including some accused of having connections to the criminal gangs known as triads. Austin Ramzy, New York Times, "Hong Kong Protests Spread to Airport as City Fears More Unrest," 26 July 2019

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

27 Aug 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

Comments on triad

What made you want to look up triad? Please tell us where you read or heard it (including the quote, if possible).


formidable, illustrious, or eminent

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