| Noun | 1. | tercet - the cardinal number that is the sum of one and one and one3, deuce-ace, III, ternary, ternion, terzetto, three, threesome, trey, triad, trine, trinity, trio, triplet, troika, tierce, leash digit, figure - one of the elements that collectively form a system of numbers; "0 and 1 are digits" | |