(adjective) : dī-mĭdĭus, a, um, medius
* Half (for the diff. between it and dimidiatus, v. dimidio).
* As an adj., until the Aug. per. only in connection with pars, e. g.: dimidiam partem nationum subegit,Plaut. Curc. 3, 77; id. Aul. 4, 10, 37; id. Rud. 4, 4, 79; Lucr. 1, 618 sq.; 5, 720; Cic. N. D. 2, 40, 103; id. Rosc. Com. 11, 32; id. Fam. 13, 29, 4; Caes. B. G. 6, 31, 5; id. B. C. 1, 27; 3, 101 (twice); Sall. J. 64, 5; Suet. Caes. 42; Front. Strat. 2, 3, 21; Ov. F. 5, 122; id. Tr. 1, 2, 44 et saep.
* Since the Aug. per., esp. in poets, also with other substantives, instead of dimidiatus (v. dimidio), divided into two equal parts, halved: mullus (opp. lupus totus),Mart. 2, 37, 4: crus,Juv. 13, 95: vultus,id. 15, 57: Memnone,id. 15, 5: forma circuli,Plin. 2, 59, 60, § 150: clepsydrae,id. Ep. 6, 2, 5: labro basia dare,i. e. slightly,Mart. 2, 10 and 22; so of busts: Priapus,Mart. 11, 18; cf. Cicero's pun on the half-length likeness of his brother Quintus: frater meus dimidius major est quam totus, in Macr. S. 2, 3 (the word dimidius, for dimidiatus, belongs prob. to Macr. himself).
* Trop., so of persons of mixed descent: dimidius patrum, dimidius plebis,half patrician and half plebeian,Liv. 4, 2, 6. —Hence, subst.
* Dīmidium, ii, n., the half (very freq. in all periods and kinds of writing): horae, Lucil. ap. Gell. 3, 14, 11; so with gen., Plaut. Am. 5, 1, 73; id. Bacch. 5, 2, 67; 71 et saep.; absol., Plaut. Bacch. 2, 3, 87; id. Ps. 4, 7, 68; 5, 2, 29; id. Pers. 1, 2, 17 et saep.; abl. dimidio, with comparatives: dimidio minus opinor,less by half,Plaut. As. 2, 4, 35; Cic. Att. 9, 9, 2; id. Fl. 20, 46; Cic. Verr. 2, 3, 33; Caes. B. G. 5, 13, 2; Hor. S. 2, 3, 318 et saep.
* Like a comp. with quam: vix dimidium militum quam quod acceperat successori tradidit,Liv. 35, 1, 2; 45, 18, 7.—Prov.: dimidium facti, qui coepit, habet,well begun is half done,Hor. Ep. 1, 2, 40; cf. Aus. Ep. 81.
* Rarely dī-midia, ae, f. (sc. pars), the half: verbenaca decocta in aqua ad dimidias,Plin. 26, 12, 73, § 120.

s. TLL