LATIN DICTIONARYLexicon Latīnum
adjectivefirst/second-declension adjective

improbus

improbus (feminine improba, neuter improbum, comparative improbior, superlative improbissimus, adverb improbē)
Classical[ˈɪm.prɔ.bʊs]Ecclesiastical[ˈim.pro.bus]
Mille Verba core vocabulary

Meaning

  1. adjectiveexcessive, immoderate, flagrant, impudent
  2. adjectivegreedy, wanton, ravenous
  3. adjectivewicked, bad, villainous, immoral, impious, malicious, cruel, unprincipled, shameless
    [...] Dabis, improbe, poenās.“You will be given — wicked [man]! — [your] punishments.” (Translations — Mackail, 1885: “Wretch, thou shalt repay!”; Knight, 1956: “You will have your punishment, you villain.”; Mandelbaum, 1971: “Depraved, you will then pay your penalties.”; Fitzgerald, 1981: “You will pay for this, unconscionable!”; West, 1990: “You will receive the punishment you deserve.”; Lombardo, 2005: “You will pay, you despicable liar,”; Fagles, 2006: “You’ll pay, you shameless, ruthless —”; Ahl, 2007: “There'll be no impunity. You'll pay.”; Ferry, 2017: “...wicked one. You will be punished.”; Bartsch, 2020: “Wicked man, you’ll pay.”; Ruden, 2021: “when you, at last, are paying.”)29 BCE – 19 BCE, Vergilius, Aeneis 4.386
  4. adjectiveindomitable

Latīnē defined in Latin in our graded readers

malus, nōn bonus; improbī iūstitiam nōn amant.
improbus -a -um — in Mille Verba, Basilica et Iūs

Declension

singular
formmasculinefeminineneuter
nominativeimprobusimprobaimprobum
genitiveimprobīimprobaeimprobī
dativeimprobōimprobaeimprobō
accusativeimprobumimprobamimprobum
ablativeimprobōimprobāimprobō
vocativeimprobeimprobaimprobum
plural
formmasculinefeminineneuter
nominativeimprobīimprobaeimproba
genitiveimprobōrumimprobārumimprobōrum
dativeimprobīsimprobīsimprobīs
accusativeimprobōsimprobāsimproba
ablativeimprobīsimprobīsimprobīs
vocativeimprobīimprobaeimproba

Lewis & Short A Latin Dictionary, 1879

imprŏbus (inpr-), a, um, adj. 2. inprobus,
I. not according to the standard.
I. Lit.
A. Below the standard, i. e. of bad quality, bad, poor, inferior (rare; mostly post-Aug.): merces, Plaut. Rud. 2, 3, 43: opera araneorum et textura inproba, id. Stich. 2, 2, 24: panis, Mart. 10, 5, 5: improbiores postes, Plaut. Most. 3, 2, 139: tua sum opera et propter te inprobior, id. Bacch. 5, 2, 84.—
B. Above or beyond the standard, i. e. enormous, monstrous, excessive: genua, Col. 6, 1, 3: arva, Val. Fl. 1, 510; 2, 631 (cf. Forbig. ad Verg. G. 1, 119; Orell. ad Hor. C. 3, 9, 22): Chilones a labris improbioribus, Charis. p. 78 P.: mons, Verg. A. 12, 687: tegmina plantae, Val. Fl. 6, 702: improbo somno, quem nec tertia saepe rumpit hora, Mart. 12, 18, 13: villus barbarum in capris, Plin. 12, 17, 37, § 73: reptatus (vitium), id. 14, 1, 3, § 13; Stat. Th. 6, 838: imber improbior, Sen. Q. N. 4, 4 fin. (in Sall. ap. Non. 366, 13; Hist. Fragm. 4, 40 Dietsch, the true read. is in prora).—
II. Transf., of mind and character.
A. Restless, indomitable, persistent (cf.: pervicax, perstans, vehemens, acer): labor omnia vincit improbus, Verg. G. 1, 146: tum cornix plena pluviam vocat improba voce, id. ib. 1, 388: quatit improbus hastam, id. A. 11, 767; cf. Hor. C. 3, 9, 23; Mart. 1, 105, 2; Ov. Tr. 1, 11, 41.—
B. Morally bad; wicked, reprobate, abandoned, vile, base, impious, ungodly, unjust, dishonest; bold, shameless, impudent; violent, fierce, outrageous (syn.: malus, malignus, pravus, depravatus, nequam).
1. Of living beings: NI TESTIMONIVM FARIATVR IMPROBVS INTESTABILISQVE ESTO, Fragm. XII. Tab. ap. Gell. 15, 13 fin.: qui improbi essent et scelesti, Plaut. Mil. 3, 1, 137: nequam et improbus, Cic. Deiot. 7, 21: illud vero improbi esse hominis et perfidiosi, id. de Or. 2, 73, 297: Cresphontes, Enn. ap. Auct. Her. 2, 24, 38 (Trag. v. 156 Vahl.): populum aut inflammare in improbos aut incitatum in bonos mitigare, Cic. de Or. 1, 46, 202: longe post natos homines improbisssimus, id. Brut. 62, 224: cum in me tam improbus fuit, id. Att. 9, 15, 5: ab ingenio est improbus, Plaut. Truc. 4, 3, 59: ut alias res est impense improbus, id. Ep. 4, 1, 39: negat improbus et te Neglegit, aut horret, Hor. Ep. 1, 7, 63: anus, id. S. 2, 5, 84: cum eum, qui sit improbus, latronem dicimus, Quint. 8, 4, 1; 1, 8, 21: (anguis) piscibus atram inprobus ingluviem explet, voracious, Verg. G. 3, 431: lupus, id. A. 9, 62: Jovis ales, id. ib. 12, 250: annis, by his youth, Juv. 3, 282: Fortuna arridens infantibus, mischievous, id. 6, 605. — Comp.: inprobior satiram scribente cinaedo, Juv. 4, 106. — *
(b). With gen.: conubii, Stat. Th. 7, 300. —
2. Of inanim. and abstr. things: improbo Iracundior Hadria, Hor. C. 3, 9, 22: lavit improba taeter Ora (leonis) cruor, Verg. A. 10, 727: perfricare faciem et quasi improbam facere, shameless, impudent, Quint. 11, 3, 160; cf.: oris improbi homo, Suet. Gramm. 15: divitiae, Hor. C. 3, 24, 62: improba non fuerit si mea charta, dato, Mart. 8, 24, 2: satureia, exciting lust, id. 3, 75, 4: ingenio improbo, Plaut. Ps. 1, 2, 16: facta, id. Truc. 2, 7, 4: dicta, licentious, Ov. F. 5, 686: verba, id. A. A. 3, 796; cf. carmina, id. Tr. 2, 441: legis improbissimae poena, Cic. Fam. 14, 4, 2: testamentum, illegal, Cic. Verr. 2, 1, 42, § 107: mala et improba defensio, id. ib. 2, 2, 41, § 101: amor, Verg. A. 4, 412; Hor. S. 1, 3, 24 (cf.: improbus, turpis, Schol. Cruq. ad loc.): spes, Quint. 12, 1, 13: improba ventris rabies, Verg. A. 2, 356: quo apertior adulatio, quo improbior, hoc citius expugnat, Sen. Q. N. 4 praef. med.: improba quamvis gratia fallaci praetoris vicerit urna, Juv. 13, 3.—Adv., in two forms, imprŏbē (class.) and improbĭter (perh. only once in Petr. 66).
1. Beyond measure, immoderately, enormously (very rare): ad eos, quibus intestinum improbe prominet, Marc. Emp. 31 med.: de quodam procerae staturae improbiusque nato, i. e. uncommonly well furnished, Suet. Vesp. 23: Chilones improbius labrati, Charis. p. 78 P. —
2. (Acc. to II.) Badly, wrongly, improperly: multa scelerate, multa audacter, multa improbe fecisti, Cic. Rosc. Am. 36, 104: facere aliquid, Quint. 1, 3, 13: quibus improbe datum est, Cic. Off. 2, 22, 79: quid ego miror, si quid ab improbis de me improbe dicitur? id. Sull. 10, 30: praeda improbe parta, id. Fin. 1, 16, 51: aliquid petere, Quint. 6, 3, 95: non improbe litigabunt, id. 12, 7, 5: ignorantia et inscitia improbe dicentium, quae non intellegunt, incorrectly, Gell. 15, 5, 1; so with indocte, id. 15, 9, 4.—Comp.: estne aliquid, quod improbius fieri possit? Cic. Verr. 2, 3, 60, § 140: decerpere oscula, Cat. 68, 126. — Sup.: quas (res) improbissime fecit, Cic. Caecin. 9, 23: respondere, id. Pis. 6, 13.

Origins

From Proto-Italic *əmproβwos. Equivalent to in- + probus. Cognate with Oscan amprufid.

Quick answers

What does improbus mean in Latin?
improbus, a adjective, means “excessive, immoderate, flagrant, impudent; greedy, wanton, ravenous; wicked, bad, villainous, immoral, impious, malicious, cruel, unprincipled, shameless”.
How do you pronounce improbus?
In classical Latin, [ˈɪm.prɔ.bʊs]; in ecclesiastical (church) Latin, [ˈim.pro.bus].