| Noun | 1. 3 - the cardinal number that is the sum of one and one and onetercet, ternary, ternion, terzetto, three, threesome, trey, triad, trine, trinity, trio, triplet, deuce-ace, III, leash, troika, tiercedigit, figure - one of the elements that collectively form a system of numeration; "0 and 1 are digits" | Adj. | 1. 3 - being one more than two iii, threecardinal - being or denoting a numerical quantity but not order; "cardinal numbers" |