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1. The cardinal number that is the sum of one and one and one
   - three, 3, III, threesome, tierce, leash, troika, triad, trine, trinity, ternary, ternion, triplet, tercet, terzetto, trey, deuce-ace
    
2. A musical composition for three performers
    
3. Three performers or singers who perform together
    
4. A set of three similar things considered as a unit
   - triad, triplet, triple
    
5. Three people considered as a unit
   - threesome, triad, trinity

Derived forms: trios

Type of: assemblage, composition, digit, figure, gathering, musical composition, musical group, musical organisation [Brit], musical organization, opus, piece, piece of music, set

Encyclopedia: Trio