1. (n.)trey a playing card or a die having three pips.
Etymology: (1350–1400; ME < MF trei(s) < L trēsthree)
Definition of 'TREY'
Princeton's WordNet
1. (noun)three, 3, III, trio, threesome, tierce, leash, troika, triad, trine, trinity, ternary, ternion, triplet, tercet, terzetto, trey, deuce-ace the cardinal number that is the sum of one and one and one
2. (noun)trey, three one of four playing cards in a deck having three pips
Definition of 'TREY'
Webster Dictionary
1. (noun)TREY three, at cards, dice, or dominoes; a card, die, or domino of threespots or pips
Definitions of TREY 
