I.nom. sing. masc. illuster. Val. Max. 4, 1, 5; 4, 3, 11), adj. inlustro, lighted up, clear, bright, light, lustrous (class.; esp. freq. in the trop. signif.).
I. Lit.: ostendebat Carthaginem de excelso et pleno stellarum, illustri et claro quodam loco, Cic. Rep. 6, 11; cf.: “tum nec nimis illustres nec vehementer obscuros locos haberi oportet,” Auct. Her. 3, 19, 32: “locus,” Cels. 3, 6: “habitare bonis et illustribus domiciliis,” Cic. N. D. 2, 37, 95: “balnearia,” Col. 1, 6, 2: “illustris et pellucida stella,” Cic. Div. 1, 57, 130: “radii solis,” Plin. 18, 35, 78, § 344: “noctes,” id. 9, 16, 23, § 56: “caelum,” Val. Fl. 6, 528.—Comp.: “ostio et lumine illustriore,” Varr. R. R. 3, 5, 5; cf.: “solis candor illustrior est quam ullius ignis,” Cic. N. D. 2, 15, 40: “(ventus) tegulas illustriores fecit,” Plaut. Rud. 1, 1, 6.—
II. Trop.
A. Clear, plain, distinct, evident, manifest (syn. clarus): “praeter haec, quae testata sunt et illustria, habeo multa occultiora,” Cic. Fam. 11, 27, 6: “his rationibus tam certis tamque illustribus, etc.,” id. Rep. 1, 3; cf.: “illustribus igitur rebus insistis ... a certis et illustrioribus cohibes assensum,” id. Ac. 2, 29, 94: “nec vero ita disseram de re tam illustri tamque nota, ut, etc.,” id. Rep. 1, 24 Mos.: “factum illustre notumque omnibus,” Cic. Verr. 2, 5, 13, § 34: “visus insignis et illustris,” id. N. D. 1, 2, 15 fin.: “illustris oratio est, si, etc. ... est enim haec pars orationis, quae rem constituat paene ante oculos ... est plus aliquanto illustre quam illud dilucidum: altero fit, ut intelligamus, altero vero ut videre videamur,” id. Part. Or. 6, 20: “si desit illustris explanatio, propositio, etc.,” Quint. 9, 2, 2: “instruenda est vita exemplis illustribus,” Sen. Ep. 83.—
B. Distinguished, respectable, famous, honorable, illustrious (cf.: “clarus, insignis, spectabilis, nobilissimus, celeber, inclutus): homines illustres honore ac nomine,” Q. Cic. Petit. Cons. 5, 18: “illustrium hominum aetates et tempora persequi (shortly after: de clarorum virorum laudibus),” Cic. Brut. 19, 74: “illustribus in personis temporibusque,” id. Rep. 2, 31 fin.: “orator,” id. Brut. 32, 122: “poëtae,” Quint. 5, 11, 36: “florens et illustris adulescens,” Caes. B. G. 7, 32, 4: “de antiquis illustrissimus quisque pastor erat,” Varr. R. R. 2, 1, 6: “philosophorum illustrissimi,” Gell. 18, 7, 3: “feminae,” noble, Suet. Tib. 45; id. Calig. 36: “cum illustribus provinciarum,” id. Caes. 48: “quorundam illustrium exsequiae,” id. Tib. 32: “paterfamiliae illustriore loco natus,” Caes. B. G. 6, 19, 3: “Themistoclis nomen est quam Solonis illustrius,” Cic. Off. 1, 22, 75: “vitae ratio illustrior,” id. Rep. 3, 3; cf.: “sunt illustriora quae publice fiunt,” id. ib. 3, 12: “haec vides quanto expressiora quantoque illustriora futura sint,” id. Fam. 1, 7, 9: “major atque illustrior res,” more important, more remarkable, Caes. B. G. 7, 3, 2: “causarum illustrium quascumque defendi nunc conficio orationes,” Cic. de Sen. 11, 38.—Hence, adv. (acc. to II. A.), clearly, distinctly, perspicuously (very rare; only comp. and sup.): “illustrius,” Cic. Fam. 10, 19, 1; id. Dom. 11, 27; Arn. 2, 44: “illustrissime descripsit,” Gell. 9, 13, 4.
