C / concŭbĭus
adjective

concŭbĭus

fem. concŭbia · neut. concŭbium
belonging to lying in sleep; to the time of sleep
of or belonging to lying in sleep, or to the time of sleep.
at the time of the first sleep, in the first sleep
As adj. only in the connection concubiā nocte (rarely: nocte concubiā, nocte in concubiā, noctu concubiā; v. the foll.), at the time of the first sleep, in the first sleep, Sisenn. ap. Non. p. 91, 22 (primi somni, Non.); Cic. Div. 1, 27, 57; Liv. 25, 9, 8; Tac. H. 3, 69; Just. 22, 8, 8: nocte concubiā, Tac. A. 1, 39: nocte in concubiā, Plin. 29, 6, 34, § 110: noctu concubiā, Enn. ap. Macr. S. 1, 4 (Ann. v. 170 Vahl.).—
that part of the night in which the first sleep falls upon men
As subst.: concŭbĭum, ii, n. (sc. tempus), that part of the night in which the first sleep falls upon men: si ante lucem occupias ... concubium sit noctis prius quam, etc., Plaut. Trin. 4, 2, 44: concubium appellarunt, quod omnes fere tunc cubarent, Varr. L. L. 6, § 7 Müll.; cf. id. ib. 7, § 78 ib.; Censor. de Die Nat. 24; Macr. S. 1, 3 fin.; Serv. ad Verg. A. 2, 268.—Hence,
coition
= concubitus, coition (perhaps only in the foll. exs.), Enn. ap. Non. p. 342, 23 (Trag. v. 241 Vahl.); Gell. 9, 10, 4.