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trīmus, a, um, adj. [tres], of three years, three years old: filia, trima quae periit mihi, Plaut. Rud. 3, 4, 39; cf.: utrumne in pulvere, trimus, Quale prius ludas opus, when a child of three years, Hor. S. 2, 3, 251: vaccae, Varr. R. R. 2, 5, 13: vaccae aetatis trimae, Pall. Mart. 11, 5: equulus, Varr. R. R. 2, 7, 13: equa, Hor. C. 3, 11, 9: arbor, Plin. 17, 11, 16, § 83: semen, id. 18, 24, 54, § 195: calx, id. 36, 23, 55, § 176.
In law: dies, a term of three years: si ita sit legatum, heres meus Titio decem trimā die dato, utrum pensionibus an vero post triennium debeatur? Dig. 33, 1, 3, § 5 sq.; cf. ib. prooem.; hence: melius post trimum domatur equulus, Varr. R. R. 2, 7, 13: capri ante trimos minus utiliter generant, Plin. 8, 50, 76, § 200.