Lewis & Short

sĕnesco, nŭi, 3 (gerundive: senescendi homines, Varr. L. L. 6, § 11 Müll. N. cr.), v. inch. n. [seneo], to grow old, become aged; to grow hoary.

  1. I. Lit. (rare): ita sensim aetas senescit, Cic. Sen. 11, 38; cf.: tempora labuntur tacitisque senescimus annis, Ov. F. 6, 771: senescente jam Graeciā, Cic. Rep. 1, 37, 58: solve senescentem mature equum, Hor. Ep. 1, 1, 8: arbores senescunt, Plin. 16, 27, 50, § 116: Solon significat se cottidie aliquid addiscentem senescere. Val. Max. 8, 7, 14.
    In perf.: avus (Augusti) tranquillissime senuit, Suet. Aug. 2: ego senui et progressioris aetatis sum, Vulg. Josne, 23, 2.
    In gerundive: longissimum spatium senescendorum hominum id (seclum) putarant, Varr. L. L. 6, § 11 Müll. N. cr.
  2. II. Transf.
    1. A. For the usual consenescere, to grow old or gray in an occupation, etc., i. e. to linger too long over it: inani circa voces studio senescunt, Quint. 8, prooem. § 18.
    2. B. (Causa pro effectu.) To decay or diminish in strength; to grow weak, feeble, or powerless; to waste away, fall off, wane, decline, etc. (the prevailing signif. of the word in prose and poetry; cf. consenesco; while inveterasco is to grow better by age).
      1. 1. Of living subjects (a favorite expression of Livy; perh. not in Cic., but cf. consenesco, II. 2.): Hannibalem jam et famā senescere et viribus, Liv. 29, 3 fin.; cf. of the same, id. 22, 39: otio senescere, id. 25, 7: non esse cum aegro senescendum, id. 21, 53: dis hominibusque accusandis senescere, to pine away, id. 5, 43 Drak.; cf.: amore senescit habendi, Hor. Ep. 1, 7, 85: socordiā, Tac. A. 1, 9; Val. Max. 8, 13, 7: ne (agni) desiderio senescant, Varr. R. R. 2, 2, 17.
        Of doves, Col. 8, 8, 4: quod antiquatur et senescit prope interitum est, Vulg. Heb. 8, 13.
      2. 2. Of things: quaedam faciunda in agris potius crescente lunā quam senescente, in the waning of the moon, Varr. R. R. 1, 37, 1; so, luna (opp. crescens), Cic. N. D. 2, 37, 95; Plin. 2, 9, 6, § 42: arbores hiemali tempore cum lunā simul senescentes, Cic. Div. 2, 14, 33: nunc pleno orbe, nunc senescente (al. senescentem) exiguo cornu fulgere lunam, Liv. 44, 37: continuā messe senescit ager, becomes exhausted, worn out, Ov. A. A. 3, 82: prata, Plin. 18, 28, 67, § 259: uniones, i. e. grow pale or dim, id. 9, 35, 56, § 115; cf. smaragdi, id. 37, 5, 18, § 70: caseus in salem, grows salt with age, id. 11, 42, 97, § 242: coma, falls out, Domit. ap. Suet. Dom. 18 fin.: monumenta virūm, decay (with delapsa), Lucr. 5, 312 et saep.: mensis senescens, drawing to an end, closing, Varr. L. L. 6, § 10 Müll.; so, hiems, Cic. N. D. 2, 19, 49.
        Of abstr. things: oratorum laus senescit, Cic. Tusc. 2, 2, 5; cf.: ut laus senescens, id. de Or. 2, 2, 7: senescere civitatem otio, Liv. 1, 22, 2: omnia orta occidunt et aucta senescunt, Sall. J. 2, 3; cf. Fabri ad Sall. C. 20, 10; so, somnia, Sall. J. 35, 3: vires, id. H. Fragm. 3, 22, p. 235 Gerl.; Liv. 9, 27: Hannibalis vis, id. 25, 16: bellum, id. 28, 36; 30, 19: pugna, id. 5, 21: fama, id. 27, 20; Tac. H. 2, 24; cf. rumores, id. A. 2, 77: consilia, Liv. 35, 12: vitia (opp. maturescente virtute), id. 3, 12: invidia, id. 29, 22: fortuna (opp. florere), Vell. 2, 11, 3: amor, Ov. A. A. 3, 594.