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perspĭcax, ācis, adj. [perspicio], sharp -sighted, penetrating, acute, perspicacious: perspicax prudentia, old poet ap. Cic. Off. 3, 26, 98: homo (with astutus), Ter. Heaut. 5, 1, 1: ad aliquam rem, id. ib. 2, 3, 129: sequemur et id, quod acutum et perspicax naturā est, Cic. Off. 1, 28, 100: ales oculis perspicax, unguibus pertinax, App. de Deo Soc. p. 108 Hildebr.; cf. id. Mag. 53: homo perspicacior Lynceo vel Argo et oculus totus, App. M. 2, p. 124, 38.
Adv.: perspĭcācĭter, acutely, sharp-sightedly, Amm. 26, 6, 1; 29, 1, 38.
Comp.: perspicacius, Consol. Phil. 3 Boëth.; id. Metr. 11, 5.