Lewis Short
gĕmellus | gĕmellus, i (noun M) :
* Adj. dim. [geminus], born at the same time, twin-born, twin- (mostly poet.; cf. geminus).
* Lit.
* Adj.: flebat avus Phoebeque soror fratresque gemelli,Ov. H. 8, 77: proles,id. ib. 6, 121; id. M. 9, 453: fetus,id. H. 6, 143: partus,id. M. 6, 712; Vulg. Cant. 4, 2.
* Transf.
* In gen., paired, double: poma cohaerentia et gemella,Plin. 15, 14, 15, § 51: vites,that have two clusters on one stalk,id. 14, 2, 4, § 21 (for which: geminae vites,Col. 3, 2, 10): gemella legio,formed out of two legions,Caes. B. C. 3, 4, 1; cf. geminus, II. A.
* Resembling or like, as twins: par nobile fratrum, Nequitia et nugis pravorum et amore gemellum,Hor. S. 2, 3, 244: pinus,Mart. 10, 92, 3: uniones,id. 12, 49, 12.
Charlton T. Lewis, Charles Short, A Latin Dictionary