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hinnĭenter, adv., v. hinnio fin.
hinnĭo, īre (perf. hinnisset, Val. Max. 7, 3, ext. 2), v. n., to neigh, whinny: ut si finias equum, genus est animal, species mortale, differentia irrationale (nam et homo mortale erat), proprium hinniens, Quint. 7, 3, 3; Lucr. 5, 1077; Quint. 1, 5 fin.: hinnientium dulcedines, i. e. of horses, Laev. ap. App. Mag. p. 294.
Poet., of the centaur Chiron, Sid. Carm. 14, 29.
Hence, * hinnĭenter, adv., with neighing: hinnibunde pro hinnienter, Non. 122, 13.