tríocha, num. s. & a. Thirty. 1. m. (gs. ~d, pl. ~idí) (In counting) ~ a haon, ~ a dó, thirty-one, thirty-two. Ceithre bliana ~d, ceithre bliana is ~, thirty-four years. An cúigiú háit is ~, the thirty-fifth place. Na ~idí, the thirties. 2. (Followed by noun in ns.) (a)~ fear, bean, bliain, slat, thirty men, women, years, yards. (b)Hist:~ céad, large territorial division, barony.