Lewis & Short

Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.

ingrātĭa, ae, f. [ingratus].

  1. I. Thanklessness, ingratitude: in ingratiam incidere, Tert. Poen. 1: hominum, id. ib. 2.
    Hence,
  2. II. ingrātĭīs, or contr. ingrātīs (v. Zumpt ad Cic. Verr. 2, 4, 9, § 19), without one’s thanks, against one’s will.
    1. A. As subst. (rare, and not in class. Lat.): tuis ingratiis ( = te invito), Plaut. Merc. 2, 4, 11; so perh. ingratiis nostris, Gell. 17, 1, 7.
      With gen.: vobis invitis atque amborum ingratiis, Plaut. Cas. 2, 5, 7.
    2. B. Adv., unwillingly, against his (her, etc.) will (class., and in both forms): id quod odio’st faciundum’st cum malo atque ingratiis, Plaut. Mil. 3, 1, 153; id. ib. 2, 5, 39; id. Am. 1, 1, 215; id. Curc. 1, 1, 6; id. Cist. 2, 3, 82; id. Men. 5, 8, 5; Ter. Heaut. 3, 1, 37; id. Eun. 2, 1, 14; id. Phorm. 5, 6, 48: ingratis, Lucr. 3, 1069; 5, 44; Lact. 2, 10, 25: extorquendum est invito atque ingratiis, Cic. Quint. 14, 47: dicent quae necesse erit, ingratiis, id. Verr. 2, 4, 9, § 19 Halm (Zumpt, ingratis): nisi plane cogit ingratiis, id. Tull. § 5; cf.: ut ingratis ad depugnandum omnes cogerentur, against their will, Nep. Them. 4, 4; so, cogere, also App. M. 2, p. 123, 39.
      See Hand, Turs. III. p. 379 sq.

ingrātĭīs and ingrātīs, v. ingratia, II.