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† agnŏs, i, f., = ἄγνος (cf. ἁγνός, chaste), a tall plant resembling the willow, the chastetree: agnus castus, Plin. 24, 9, 38, § 59.
agnus, i, m. (gen. plur. agnūm, Porc. Licin. ap. Gell. 19, 9, 13) [cf. ἀμνός, which Benfey connects with ὄϊς = Sanscr. avis; Lith. ávinas = sheep], a lamb, usually for sacrifice: TERTIA. SPOLIA. IANO. QVIRINO. AGNOM. MAREM. CAEDITO, from an ancient law (of Numa?), in Fest. s. v. opima, p. 190: IVNONI. CRINIBVS. DEMISSIS. AGNAM. FEMINAM. CAEDITO., from a law of Numa in Gell. 4, 33, and Fest. s. v. pellices, p. 121: jam ego te hic agnum faciam et medium distruncabo, Plaut. Truc. 2, 7, 54; Varr. R. R. 2, 2, 4 al.: agnus absque maculā, Vulg. Exod. 12, 5: agnos immaculatos, ib. Lev. 14, 10: villa abundat porco, haedo, agno, Cic. Sen. 16, 56; id. Div. 2, 11, 39; Ov. M. 7, 320; Hor. C. 3, 18, 13: ara avet immolato Spargier agno, id. ib. 4, 11, 8 al.
Prov.: Agnum lupo eripere velle, to wish to rescue a lamb from a wolf, i. e. to wish what is impossible, Plaut. Poen. 3, 5, 31.
Eccl. Lat., of Christ: quasi agni immaculati Christi, Vulg. 1 Pet. 1, 19: Ecce Agnus Dei, ib. Joan. 1, 29: ceciderunt coram Agno, ib. Apoc. 5, 8 al.