'Triad' definitions:

Definition of 'triad'

(from WordNet)
noun
The cardinal number that is the sum of one and one and one [syn: three, 3, III, trio, threesome, tierce, leash, troika, triad, trine, trinity, ternary, ternion, triplet, tercet, terzetto, trey, deuce- ace]
noun
A set of three similar things considered as a unit [syn: trio, triad, triplet, triple]
noun
Three people considered as a unit [syn: trio, threesome, triad, trinity]
noun
A three-note major or minor chord; a note and its third and fifth tones [syn: common chord, triad]

Definition of 'Triad'

From: GCIDE
  • Triad \Tri"ad\, n. [L. trias, -adis, Gr. ?, ?, fr.?, ?, three: cf. F. 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. [1913 Webster]
  • 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. [1913 Webster]
  • 3. (Chem.) An element or radical whose valence is three. [1913 Webster]
  • 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.
  • Hindu triad. See Trimurti. [1913 Webster]

Synonyms of 'triad'

From: Moby Thesaurus