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1. The cardinal number that is the sum of one and one and one
   - three, 3, III, trio, threesome, tierce, leash, troika, trine, trinity, ternary, ternion, triplet, tercet, terzetto, trey, deuce-ace
    
2. A set of three similar things considered as a unit
   - trio, triplet, triple
    
3. Three people considered as a unit
   - trio, threesome, trinity
    
4. A three-note major or minor chord; a note and its third and fifth tones
   - common chord
    
5. A Chinese society or gang involved in organized crime

Derived forms: triads

Type of: assemblage, chord, digit, figure, gathering, set

Encyclopedia: Triad