Trinal \Tri"nal\, a. [L. trinus triple, trini three each, fr. tres, tria, three. See {Three}, and cf. {Trine}, a. & n., {Tern}, a.] Threefold. "Trinal unity." --Milton. [1913 Webster] In their trinal triplicities on high. --Spenser. [1913 Webster]