TRIAD
trio, threesome, triad, trinity
(noun) three people considered as a unit
trio, triad, triplet, triple
(noun) a set of three similar things considered as a unit
three, III, trio, threesome, tierce, leash, troika, triad, trine, trinity, ternary, ternion, triplet, tercet, terzetto, trey, deuce-ace
(noun) the cardinal number that is the sum of one and one and one
Source: WordNet® 3.1
Etymology
Noun
triad (plural triads)
A grouping of three.
Synonyms: threesome, trine, trinity, trio, triplet, troika, triumvirate, Thesaurus:trio
A word of three syllables.
Synonym: trisyllable
A branch of a Chinese underground criminal society, mostly based in Hong Kong.
(electronics) on a CRT display, a group of three neighbouring phosphor dots, coloured green, red, and blue.
(music) A chord consisting of a root tone, the tone two degrees higher, and the tone four degrees higher in a given scale.
Coordinate terms
• (group of three): monad · duad, dyad · triad · tetrad · pentad · hexad · heptad · octad · ennead, nonad · decad, decade · hendecad · dodecad, duodecade
• (word of four syllables): quaternion
Anagrams
• drait, iTard
Source: Wiktionary
Tri"ad, n. Etym: [L.trias, -adis, Gr. triade. See Three, and cf.
Trias, Trio.]
1. A union of three; three objects treated as one; a ternary; a
trinity; as, a triad of deities.
2. (Mus.)
(a) A chord of three notes.
(b) The common chord, consisting of a tone with its third and fifth,
with or without the octave.
3. (Chem.)
Definition: An element or radical whose valence is three. Triads of the
Welsh bards, poetical histories, in which the facts recorded are
grouped by threes, three things or circumstances of a kind being
mentioned together.
– Hindoo triad. See Trimurti.
Source: Webster’s Unabridged Dictionary 1913 Edition