'threesome' definitions:

Definition of 'threesome'

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
Three people considered as a unit [syn: trio, threesome, triad, trinity]