threesome

详细解释:n. 三人一组, 三人的竞赛

英语解释：

名词 threesome:

the cardinal number that is the sum of one and one and one同义词：three, 3, III, trio, tierce, leash, troika, triad, trine, trinity, ternary, ternion, triplet, tercet, terzetto, trey, deuce-ace