Lewis & Short

quartus, a, um, num. adj. [for quatertus from quattuor, kindr. with Gr. τέτϝαρτος and Sanscr. caturtha, the fourth], the fourth: perfidia, et peculatus ex urbe et avaritiā si exsulant, quarta invidia, quinta ambitio, Plaut. Pers. 4, 4, 7: pars copiarum, Caes. B. G. 1, 12: quartus ab Arcesilā, the fourth from Arcesilas, Cic. Ac. 2, 6: pater, i. e. abavus, Verg. A. 10, 619: quartus decimus, the fourteenth, Tac. A. 13, 15: die quarto, on the fourth day, four days ago: nuper die quarto, ut recordor, Cn. Matius ap. Gell. 10, 24, 10.
In the future, four days hence, in the ante-class. form, die quarte (al. quarti): die quarte moriar fame, Pompon. ap. Gell. 10, 24, 5.

  1. B. Subst.
    1. 1. quarta, ae, f. (sc. pars), a fourth part, a quarter, esp. of an estate, Quint. 8, 5, 19; so Dig. 5, 2, 8; 5, 4, 3.
    2. 2. quartum, i, n., in econom. lang., the fourth grain: nam frumenta majore parte Italiae quando cum quarto responderint vix meminisse possumus, i. e. yielded a harvest of four for one, Col. 3, 3, 4.
  2. C. Advv.
    1. 1. quartum, for the fourth time (class.): Quintus pater quartum fit consul, Enn. ap. Gell. 10, 1, 6 (Ann. v. 293 Vahl.): eo quartum consule, Cic. Sen. 4, 10; v. infra: T. Quinctio quartum consule, Liv. 3, 67.
    2. 2. quartō, for the fourth time, the fourth time: ter conata loqui, ter destitit, ausaque quarto, Ov. F. 2, 823: quarto Excudit amplexus, id. M. 9, 51: Caesar dictator tertio, designatus quarto, Auct. B. Hisp. 2 init.; cf.: quarto vel quinto, four or five times, Eutr. 7, 18: aliud est quarto praetorem fieri, et quartum, quod quarto locum assignificat ac tres ante factos, quartum tempus assignificat et ter ante factum. Igitur Ennius recte, qui scripsit: Quintus pater quartum fit consul, Varr. ap. Gell. 10, 1, 6.