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jŏcus, i (plur. also joca, jocorum, n.; so always in Cic.), m. [perh. akin to Sanscr. root div, ludere; cf. jucundus], a jest, joke (class.): joci causa magistrum adhibes, for the sake of the joke, Cic. Phil. 2, 17, 42: defensio redundabat hilaritate quadam et joco, id. de Or. 2, 54, 221: ut ad ludum et jocum facti videamur, id. Off. 1, 29, 103: quicum joca seria, ut dicitur, id. Fin. 2, 26, 85: joca atque seria cum humillimis agere, Sall. J. 96, 2: seria ac jocos celebrare, Liv. 1, 4, 9: jocum accipimus quod est contrarium serio, Quint. 6, 3, 21; 68; 94: conviva joco mordente facetus, Juv. 9, 10; Plin. Ep. 2, 13, 5; Tac. A. 2, 13: agitare jocos cum aliquo, Ov. M. 3, 320; of jests of love, Hor. Ep. 1, 6, 65: seu tu querelas sive geris jocos, id. C. 3, 21, 2: materiam praebere causas jocorum, Juv. 3, 147; pastime, sport, Plin. 8, 40, 61, § 144: quibus jusjurandum jocus est, Cic. Fl. 5, 12: per jocum, in jest, by way of a joke, Plaut. Am. 3, 2, 39; id. Poen. 5, 5, 42: joco an serio haec dicat, Ter. Heaut. 3, 2, 20; Cic. Fam. 4, 4, 1.
So, too, joco quid dictum est per jocum, Plaut. Am. 2, 3, 35: ne joco quidem mentiretur, Nep. Ep. 3, 1: joco seriove, Liv. 7, 41, 3; Suet. Ner. 25; id. Aug. 53: extra jocum or remoto joco, joking aside, without joking: extra jocum, bellus est, Cic. Fam. 7, 16, 2: remoto joco, tibi praecipio, ut, etc., id. ib. 7, 11, 3: ludus et jocus, mere sport, a trifle, Liv. 28, 42: mille facesse jocos: turpe est nescire puellam Ludere, Ov. A. A. 3, 367.
Personified: quam Jocus circumvolat et Cupido, the god of jests, Hor. C. 1, 2, 34; Plaut. Bacch. 1, 2, 8.