Lewis & Short

aes, aeris (often used in plur. nom. and acc.; abl. aeribus, Cato ap. Paul. ex Fest. p. 27 Müll., and Lucr. 2, 636; gen. AERVM, Inscr. Orell. 3551), n. [cf. Germ. Eisen = iron, Erz = copper; Goth. aiz = copper, gold; Angl.Sax. ar, ær = ore, copper, brass; Eng. iron, ore; Lat. aurum; with the com. notion of brightness; cf. aurora, etc.].

  1. I. Any crude metal dug out of the earth, except gold and silver; esp.,
        1. a. Aes Cyprium, whence cuprum, copper: scoria aeris, copper dross or scoria, Plin. 34, 11, 24, § 107: aeris flos, flowers of copper, id. 34, 11, 24, § 107: squama aeris, scales of copper, Cels. 2, 12 init.: aes fundere, Plin. 33, 5, 30, § 94: conflare et temperare, id. 7, 56, 57, § 197: India neque aes neque plumbum habet, id. 34, 17, 48, § 163: aurum et argentum et aes, Vulg. Ex. 25, 3.
        2. b. An alloy, for the most part of copper and tin, bronze (brass, an alloy of copper and zinc, was hardly known to the ancients. For their bronze coins the Greeks adhered to copper and tin till B.C. 400, after which they added lead. Silver is rare in Greek bronze coins. The Romans admitted lead into their bronze coins, but gradually reduced the quantity, and, under Calig., Nero, Vesp., and Domit., issued pure copper coins, and then reverted to the mixture of lead. In the bronze mirrors now existing, which are nearly all Etruscan, silver predominated to give a highly reflecting surface. The antique bronze had about 87 parts of copper to 13 of tin. An analysis of several objects has given the following centesimal parts: [??] statua ex aere, Cic. Phil. 9, 6: simulacrum ex aere factum, Plin. 34, 4, 9, § 15: valvas ex aere factitavere, id. 34, 3, 7, § 13.
          Hence: ducere aliquem ex aere, to cast one’s image in bronze, id. 7, 37, 38, § 125; and in the same sense poet.: ducere aera, Hor. Ep. 2, 1, 240: aes Corinthium, Plin. 34, 2, 3, §§ 5-8; v. Corinthius.
  2. II. Meton.
    1. A. (Esp. in the poets.) For everything made or prepared from copper, bronze, etc. (statues, tables of laws, money), and (as the ancients had the art of hardening and tempering copper and bronze) weapons, armor, utensils of husbandry: aes sonit, franguntur hastae, the trumpet sounds, Enn. ap. Non. 504, 32 (Trag. v. 213 Vahl.): Et prior aeris erat quam ferri cognitus usus: Aere solum terrae tractabant, aereque belli Miscebant fluctus et vulnera vasta serebant, etc., Lucr. 5, 1287: quae ille in aes incidit, in quo populi jussa perpetuasque leges esse voluit, Cic. Phil. 1, 17; cf. id. Fam. 12, 1; Tac. A. 11, 14; 12, 53; id. H. 4, 40: aere (with the trumpet, horn) ciere viros, Verg. A. 6, 165: non tuba directi, non aeris cornua flexi, Ov. M. 1, 98 (hence also rectum aes, the tuba, in contr. with the crooked buccina, Juv. 2, 118); a brazen prow, Verg. A. 1, 35; the brazen age, Hor. Epod. 16, 64.
      In plur.: aera, Cato ap. Paul. ex Fest. p. 27 Müll.; Verg. A. 2, 734; Hor. C. 4, 8, 2 al.
    2. B. Money: the first Roman money consisted of small rude masses of copper, called aes rude, Plin. 33, 3, 13, § 43; afterwards as coined: aes signatum, Cic. Leg. 3, 3; Plin. 33, 3, 13, § 43; so aes alone: si aes habent, dant mercem, Plaut. As. 1, 3, 49: ancilla aere suo empta, Ter. Phorm. 3, 2, 26: aes circumforaneum. borrowed from the brokers in the forum, Cic. Att. 2, 1: Hic meret aera liber Sosiis, earns them money, Hor. A. P. 345: gravis aere dextra, Verg. E. 1, 36: effusum est aes tuum, Vulg. Ez. 16, 36: neque in zona aes (tollerent), ib. Maarc. 6, 8: etiam aureos nummos aes dicimus, Dig. 50, 16, 159.
      Hence,
      1. 1. Aes alienum, lit. the money of another; hence, in reference to him who has it, the sum owed, a debt, Plaut. Curc. 3, 1, 2: habere aes alienum, Cic. Fam. 5, 6: aes alienum amicorum suscipere, to take upon one’s self, id. Off. 2, 16: contrahere, to run up, id. Q. Fr. 1, 1, 8: facere, id. Att. 13, 46: conflare, Sall. C. 14, 2; 24, 3: in aes alienum incidere, to fall into debt, Cic. Cat. 2, 9: in aere alieno esse, to be in debt, id. Verr. 2, 2, 4, § 6; so, aere alieno oppressum esse, id. Font. 1; so Vulg. 1 Reg. 22, 2: laborare ex aere alieno, Caes. B. C. 3, 22: liberare se aere alieno, to get quit of, Cic. Att. 6, 2; so, aes alienum dissolvere, id. Sull. 56: aere alieno exire, to get out of, id. Phil. 11, 6.
      2. 2. In aere meo est, trop., he is, as it were, among my effects, he is my friend (only in the language of common conversation): in animo habui te in aere meo esse propter Lamiae nostri conjunctionem, Cic. Fam. 13, 62; 15, 14.
      3. * 3. Alicujus aeris esse, to be of some value, Gell. 18, 5.
      4. * 4. In aere suo censeri, to be esteemed according to its own worth, Sen. Ep. 87.
    3. C. Sometimes = as, the unit of the standard of money (cf. as); hence, aes grave, the old heary money (as weighed, not counted out): denis milibus aeris gravis reos condemnavit, Liv. 5, 12: indicibus dena milia aeris gravis, quae tum divitiae habebantur, data, id. 4, 60; so, aes alone and in the gen. sing., instead of assium: aeris miliens, triciens, a hundred millions, three millions, Cic. Rep. 3, 10: qui milibus aeris quinquaginta census fuisset, Liv. 24, 11.
      Also for coins that are smaller than an as (quadrans, triens, etc.): nec pueri credunt, nisi qui nondum aere, i. e. quadrante, lavantur (those who bathed paid each a quadrans), Juv. 2, 152 (cf.: dum tu quadrante lavatum Rex ibis, Hor. S. 1, 3, 137).
    4. D. Wages, pay.
      1. 1. A soldier’s pay = stipendium: negabant danda esse aera militibus, Liv. 5, 4. And soon after: annua aera habes: annuam operam ede.
        Hence in plur., = stipendia, Cic. Verr. 2, 5, 13, § 33.
      2. 2. Reward, payment, in gen., Juv. 6, 125: nullum in bonis numero, quod ad aes exit, that has in view or aims at pay, reward, Sen. Ep. 88.
    5. E. In plur.: aera, counters; hence also the items of a computed sum (for which, later, a sing. form aera, ae (q. v.), came into use): si aera singula probāsti, summam, quae ex his confecta sit, non probare? Cic. ap. Non. 3, 18.