Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
crībro, āvi, ātum, 1, v. a. [cribrum], to pass through a sieve, to sift (perh. not anteAug.), Col. 12, 51, 1; Plin. 17, 11, 15, § 76 al.
crībrum, i, n. [from root cer, whence cerno], a sieve, searce, riddle, Cato, R. R. 25, 76, 3; Plaut. Rud. 1, 2, 14; Cic. Div. 2, 27, 59; Col. 8, 5, 16; Plin. 18, 11, 28, § 108 sq.; Ov. M. 12, 437; Pers. 3, 112 et saep.
Facete, of a slave whose back was pierced by goads: carnificum cribrum, Plant. Most. 1, 1, 52.
Prov.: imbrem in cribrum gerere, i. e. to labor in vain, Plaut. Ps. 1, 1, 100.