Lewis & Short

2. ĕō, adv. [old dat. and abl. form of pron. stem i; cf. is].

  1. I. In locat. and abl. uses,
    1. A. Of place = in eo loco, there, in that place (rare): quid (facturus est) cum tu eo quinque legiones haberes? Cic. Ep. ad Brut. 1, 2, 1: quo locoibieoque, Cels. 8, 9, 1: eo loci, Tac. A. 15, 74; Plin. 11, 37, 50, § 136; so trop.: eo loci, in that condition: res erat eo jam loci, ut, etc., Cic. Sest. 13, 68; Tac. A. 14, 61; Dig. 5, 1, 52, § 3.
    2. B. Of cause = eā re.
      1. 1. Referring to a cause or reason before given, therefore, on that account, for that reason: is nunc dicitur venturus peregre: eo nunc commenta est dolum, Plaut. Truc. 1, 1, 66; Ter. Hec. 2, 1, 41: dederam litteras ad te: eo nunc ero brevior, Cic. Fam. 6, 20, 1; Sall. C. 21, 3; Liv. 8, 8, 8; Tac. H. 2, 65; Nep. Pelop. 1, 3; id. Milt. 2, 3 et saep.
        So with conjunctions, eoque, et eo, eo quoque, in adding any thing as a consequence of what precedes, and for that reason: absolute pares, et eo quoque innumerabiles, Cic. Ac. 2, 17, 55: impeditius eoque hostibus incautum, Tac. A. 1, 50: per gentes integras et eo feroces, Vell. 2, 115, 2; Quint. 4, 1, 42 al.
      2. 2. Referring to a foll. clause, giving
          1. (α) a cause or reason, with quia, quoniam, quod, etc.; so with quia: eo fit, quia mihi plurimum credo, Plaut. Am. 2, 2, 124; id. Capt. 1, 1, 2: nunc eo videtur foedus, quia, etc., Ter. Eun. 4, 4, 17; 3, 1, 25: quia scripseras, eo te censebam, etc., Cic. Att. 10, 17, 4; Sall. C. 20, 3; Tac. Agr. 22.
            With quoniam: haec eo notavi, quoniam, etc., Gell. 7, 13.
            With quod: quodnon potueritis, eo vobis potestas erepta sit, Cic. Verr. 1, 8, 22; Nep. Eum. 11, 5; Liv. 9, 2, 4; Caes. B. G. 1, 23; so, neque eoquod, Ter. Heaut. 3, 2, 43; Varr. R. R. 1, 5.
          2. (β) A purpose, motive or reason, with quo, ut, ne; and after negatives, with quo, quin, and subj.
            So with quo: eo scripsi, quo plus auctoritatis haberem, Cic. Att. 8, 9, 1; Sall. C. 22, 2; so, non eoquo, Ter. Eun. 1, 2, 16: neque eoquo, Cic. Att. 3, 15, 4; id. Rosc. Am. 18, 51.
            With ut: haec eo scripsi, ut intellegeres, Cic. Fam. 13, 69, 2; id. de Or. 3, 49, 187; Lact. 4, 5, 9.
            With ne: Plaut. Aul. 2, 2, 63; Ter. Ph. 5, 1, 17: quod ego non eo vereor, ne mihi noceat, Cic. Att. 9, 2; id. Rab. Perd. 3, 9.
            With quin: non eo haec dico, quin quae tu vis ego velim, Plaut. Trin. 2, 2, 60; id. As. 5, 1, 16.
    3. C. Of measure or degree—with words of comparison, so much, by so much—followed by quo (= tantoquanto): quae eo fructuosiores fiunt, quo calidior terra aratur, Varr. R. R. 1, 32, 1: eo gravior est dolor, quo culpa major, Cic. Att. 11, 11, 2; id. Fam. 2, 19, 1; so with quantum: quantum juniores patrum plebi se magis insinuabant, eo acrius contra tribuni tendebant, etc., Liv. 3, 15, 2; id. 44, 7, 6: quanto longius abscederent, eo, etc., id. 30, 30, 23.
      Esp. freq. the formulae, eo magis, eo minus, so much the worse (the less), followed by quo, quod, quoniam, si, ut, ne: eo magis, quo tanta penuria est in omni honoris gradu, Cic. Fam. 3, 11, 7: eo minus veritus navibus, quod in littore molli, etc., Caes. B. G. 5, 9; Cic. Off. 3, 22, 88; id. Att. 15, 9 fin.: eo magis, quoniam, etc., Cels. praef. p. 14, 12 Müll.: nihil admirabilius fieri potest, eoque magis, si ea sunt in adulescente, Cic. Off. 2, 14, 48; id. Tusc. 1, 39, 94: eo diligentius ut ne parvula quidem titubatione impediremur, Auct. Her. 2, 8, 12; Cic. Rab. Perd. 3, 9: ego illa extuli et eo quidem magis, ne quid ille superiorum meminisse me putaret, id. Att. 9, 13, 3.
      In this combination eo often expresses also the idea of cause (cf. B. 1. supra): hoc probis pretiumst. Eo mihi magis lubet cum probis potius quam cum improbis vivere, Plaut. Trin. 2, 1, 37: solliciti tamen et anxii sunt; eoque magis, quod se ipsi continent et coercent, Cic. Tusc. 4, 33, 70; and some passages may be classed under either head: dederam triduo ante litteras ad te. Eo nunc ero brevior, Cic. Fam. 6, 21, 1; id. Inv 1, 4, 5; id. Off. 2, 13, 45; id. Fam. 9, 16, 9; Plaut. Aul. 2, 2, 8.
  2. II. In dat. uses.
    1. A. With the idea of motion, to that place, thither (= in eum locum): eo se recipere coeperunt, Caes. B. G. 1, 25, 5: uti eo cum introeas, circumspicias, uti inde exire possit, Cato, R. R. 1, 2: eo tela conicere, Auct. B. Afr. 72: eo respicere, Sall. J. 35, 10; so, followed by quo, ubi, unde: non potuit melius pervenirier eo, quo nos volumus, Ter. Phorm. 4, 3, 35: venio nunc eo, quo me fides ducit, Cic. Rosc. Am. 30, 83: ibit eo quo vis, etc., Hor. Ep. 2, 2, 40: (venit) eo, ubi non modo res erat, etc., Cic. Quint. 11; Varr. R. R. 3, 16, 21; Vell. 2, 108, 2: eo, unde discedere non oportuit, revertamur, Cic. Att. 2, 16, 3; Liv. 6, 35, 2; Sall. C. 60, 2; so (late Lat.) with loci: perducendum eo loci, ubi actum sit, Dig. 10, 4, 11, § 1; ib. 47, 2, 3, § 2.
    2. B. Transf.
      1. 1. With the idea of addition, thereto, in addition to that, besides: accessit eo, ut milites ejus, etc., Cic. Fam. 10, 21, 4: accedit eo, quod, etc., id. Att. 1, 13, 1.
      2. 2. With the idea of tendency, to that end, with that purpose, to this result: hoc autem eo spectabat, ut eam a Philippo corruptam diceret, Cic. Div. 2, 57, 118: haec eo pertinet oratio, ut ipsa virtus se sustentare posse videretur, id. Fam. 6, 1, 12: hoc eo valebat, ut, etc., Nep. Them. 4, 4.
      3. 3. With the idea of degree or extent, to that degree or extent, so far, to such a point: eo scientiae progredi, Quint. 2, 1, 6: postquam res publica eo magnificentiae venerit, gliscere singulos, Tac. A. 2, 33; id. H. 1, 16; id. Agr. 28: eo magnitudinis procedere, Sall. J. 1, 5; 5, 2; 14, 3: ubi jam eo consuetudinis adducta res est, ut, etc., Liv. 25, 8, 11; 28, 27, 12; 32, 18, 8 al.; Just. 3, 5: eo insolentiae processit, Plin. Pan. 16: eo rerum ventum erat, ut, etc., Curt. 5, 12, 3; 7, 1, 35.
        With gen., Val. Max. 3, 7, 1 al.; Flor. 1, 24, 2; 2, 18, 12; Suet. Caes. 77; Plin. Pan. 16, 5; Sen. Q. N. 4 praef. § 9: eo rem jam adducam, ut nihil divinationis opus sit, Cic. Rosc. Am. 34, 96: res eo est deducta, ut, etc., id. Att. 2, 18, 2; Hor. C. 2, 1, 226; Cic. Verr. 2, 4, 18.
    3. C. Of time, up to the time, until, so long, usually with usque, and followed by dum, donec: usque eo premere capita, dum illae captum amitterent, Cic. N. D. 2, 49, 124; Liv. 23, 19, 14; Tac. A. 4, 18: eo usque flagitatus est, donec ad exitium dederetur, id. ib. 1, 32; Quint. 11, 3, 53: eo usque vivere, donec, etc., Liv. 40, 8; cf. Col. 4, 24, 20; 4, 30, 4.
      Rarely by quamdiu: eo usque, quamdiu ad fines barbaricos veniretur, Lampr. Alex. Sev. 45.