triad

plural triads

1. A grouping of three.

   Later artworks showed many animals and gods, some of which were clearly identified with heavenly body. They often included the symbolic triad of Sun, Moon, and Venus.

   1998, John H. Roger, “Origins of the ancient constellations: I. The Mesopotamian traditions”, in Journal of the British Astronomy Association, volume 108, number 1, page 10, column 2

   1 more example

   There are, says the Irish triad, 'three fewnesses that are better than plenty: a fewness of fine words; a fewness of cows on grass; a fewness of good friends around good ale'. As an Ulsterman I would agree.

   2000, David Pierce, Irish Writing in the Twentieth Century: A Reader, page 625

   Synonyms: threesome, trine, trinity, trio, triplet, troika, triumvirate, leash

   1. A romantic or sexual relationship between three individuals; a throuple.

      Synonyms: threesome, trine, trinity, trio, triplet, troika, triumvirate, leash

2. A word of three syllables.

   In his general deportment he was pompous and important, affecting a species of florid elocution, which often became ridiculous from his misarranging the triads and quaternions with which he loaded his sentences.

   1815 February 24, [Walter Scott], chapter 13, in Guy Mannering; or, The Astrologer. […], volume (please specify |volume=I to III), Edinburgh: […] James Ballantyne and Co. for Longman, Hurst, Rees, Orme, and Brown, […]; and Archibald Constable and Co., […], →OCLC

   Synonyms: trisyllable

3. A branch of a Chinese underground criminal society, mostly based in Hong Kong.

   1 more example

   The point — and the symbolism — was that so long as the informer kept his mouth shut he was alive. Harry had seen the result of zjuk carried out by the Tapei Triad on a poor jerk they found in a back street of Tan-shui. They had used broad nail heads that didn’t make such big holes on their way in. When the paramedics came and pulled the brick off the dead man, the face came with it.

   Phantom

   2012 [2011], Jo Nesbø, translated by Don Bartlett, Gjenferd [Phantom] (Fiction), New York: Alfred A. Knopf, →ISBN, →LCCN, →OCLC, page 99

4. businessOn a CRT display, a group of three neighbouring phosphor dots, coloured green, red, and blue.
5. entertainmentA chord consisting of a root tone, the tone two degrees higher, and the tone four degrees higher in a given scale OR any chord with three notes.