Lewis Short
terni, ae, a
* Num. distr. adj. [ter].
* Lit., three each: ea partes habet novem discretas, ter ternas,Varr. R. R. 2, 1, 12; so, terni ter cyathi,Hor. C. 3, 19, 14: ut in jugera singula ternis medimnis decidere liceret,Cic. Verr. 2, 3, 48, § 114; so id. Balb. 21, 48; Caes. B. G. 3, 15 al.: ternae sunt utriusque partes,Cic. Or. 60, 201: muneraque in naves ternos optare juvencos,Verg. A. 5, 247: ternūm pedum longitudo,Plin. 11, 29, 35, § 103: ternūm digitorum,id. 20, 17, 73, § 190: cubitorum,id. 25, 6, 30, § 66; also, intervallo ternorum pedum,id. 16, 36, 67, § 173: pariunt terna ova,Col. 8, 14, 5.—In sing.: terno consurgunt ordine remi,Verg. A. 5, 120: te Gratia terna afflavit,i. e. the three Graces,Claud. Laud. Seren. 88.
* Transf., for tres, three: quid ternas (litteras)?Plaut. Merc. 2, 2, 33: tres equitum numero turmae ternique vagantur Ductores,Verg. A. 5, 560: saecula,Tib. 4, 1, 112: terna guttura monstri,Ov. M. 10, 22: immane est vitium, dare milia terna macello,Hor. S. 2, 4, 76: ter terna, quae sunt novem,Macr. Somn. Scip. 1, 6.
Charlton T. Lewis, Charles Short, A Latin Dictionary