Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
lāmenta, ae, f. (collat. form of lamentum, q. v.): lamentas, fletus facere, Pac. ap. Non. 132, 28 (Trag. Fragm. v. 175 Rib.).
lāmento, āvi, 1, v. n. (collat. form of lamentor), Vulg. Matt. 11, 17; id. Luc. 7, 32.