Lewis & Short

dēbĭlis (old shortened form debil, v. Ritschl, Opusc. Phil. 2, 331), e, adj. [de-habilis; cf. Dig. 49, 16, 4, § 12: lit. unmanageable, wanting in flexibility or activity; hence], lame, disabled, crippled, infirm, debilitated, feeble, frail, weak, etc. For syn. cf.: imbecillus, infirmus, invalidus (freq. and class.).

  1. I. Lit.
        1. a. Of personal subjects: debiles fieri, Cato R. R. 157, 10: si gladium imbecillo seni aut debili dederis, Cic. Sest. 10, 24; cf. id. Phil. 8, 10, 31; Phaedr. 4, 2, 10: confectus senectute, mancus et membris omnibus captus ac debilis, Cic. Rab. Perd. 7, 21; cf.: debilis manu, pede, coxa, Maecen. ap. Sen. Ep. 101, 11; ille humero, hic lumbis, hic coxa debilis, * Juv. 10, 227: plurimis stipendiis debilis miles, Plin. 7, 28, 29, § 104: integris debiles implicabantur, Curt. 4, 16, 11: amissis remis atque ordine debilis uno Sergestus, Verg. A. 5, 271: claudi ac debiles equi, Liv. 21, 40.
        2. b. Of inanimate subjects: membra metu, * Ter. Ad. 4, 4, 3; Sen. Contr. 5, 33; cf. debile fit corpus, Lucr. 4, 952; 5, 830: manus, Ov. M. 12, 106: crus, * Suet. Vesp. 7: ferrum, Verg. A. 12, 50: pennae, Ov. R. Am. 198: jugum, id. Pont. 3, 1, 68: umbra, id. Tr. 3, 4, 20.
          Poet.: iter, i.e. of a wounded man, Stat. Th. 12, 144.
  2. II. Trop., disabled, weak, in mind, character, authority, etc.
        1. a. Of personal subjects: eos qui restitissent infirmos sine illo (sc. Catilina) ac debiles fore putabam, Cic. Cat. 3, 2: qui hac parte animi (sc. memoria) tam debilis esset, ut, etc., id. Brut. 61, 219: ingenio debilior, Tac. H. 4, 62; cf.: sine animo anima est debilis, Att. ap. Non. 426, 48 (v. 296 Ribbeck).
        2. b. Of inanimate subjects: duo corpora esse reipublicae, unum debile, infirmo capite: alterum firmum sine capite, Cic. Mur. 25, 51: manca ac debilis praetura, id. Mil. 9, 25; id. Tusc. 2, 5, 13: manus, sine quibus trunca esset actio ac debilis, Quint. 11, 3, 85: inscitia, * Pers. 5, 99.
          Comp. v. supra.
          Sup. appears not to occur.
          * Adv., dēbĭlĭter, infirmly, lamely, feebly: lacrimis lingua debiliter stupet, Pac. ap. Non. 98, 18 (v. 355 Ribbeck).