triad

triad [trahy-ad, -uh d] ExamplesWord Origin noun

1. a group of three, especially of three closely related persons or things.
2. Chemistry.
   1. an element, atom, or group having a valence of three.Compare monad(def 2), dyad(def 3).
   2. a group of three closely related compounds or elements, as isomers or halides.
3. Music. a chord of three tones, especially one consisting of a given tone with its major or minor third and its perfect, augmented, or diminished fifth.
4. (initial capital letter) Military. the three categories of strategic-nuclear-weapons delivery systems: bombers, land-based missiles, and missile-firing submarines.

Origin of triad 1540–50; Latin triad- (stem of trias) Greek triás See tri-, -ad1 Related formstri·ad·ic, adjectivetri·ad·ism, noun Examples from the Web for triadic Historical Examples of triadic

For Kempe’s triadic relation in question can be stated, in what he calls its obverse form, in perfectly symmetrical terms.

International Congress of Arts and Science, Volume I

Various

Truth would be a triadic relation, but of a different sort from that expounded by Mr. Russell.

Essays in Experimental Logic

John Dewey

As the total system falls into three parts, so every part of the system follows the triadic law.

Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 2

Various

British Dictionary definitions for triadic triad noun

1. a group of three; trio
2. chem an atom, element, group, or ion that has a valency of three
3. music a three-note chord consisting of a note and the third and fifth above it
4. an aphoristic literary form used in medieval Welsh and Irish literature
5. the US strategic nuclear force, consisting of intercontinental ballistic missiles, submarine-launched ballistic missiles, and bombers

Derived Formstriadic, adjectivetriadism, nounWord Origin for triad C16: from Late Latin trias, from Greek; related to Greek treis three Triad noun

1. any of several Chinese secret societies, esp one involved in criminal activities, such as drug trafficking

Word Origin and History for triadic triad n.

1540s, “group or set of three,” from Late Latin trias (genitive triadis), from Greek trias (genitive triados), from treis “three” (see three). Musical sense of “chord of three notes” is from 1801.

triadic in Medicine triad [trī′ăd′, -əd] n.

1. A collection of three things or symptoms having something in common.
2. The transverse tubule, and the terminal cisternae on each side of it, in a skeletal muscle fiber.