Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
pollūbrum (pōlūbr-), i, n. [polluo], a wash-basin, laver: polubrum pelluvium vas, quod nos pelvem vocamus, Paul. ex Fest. p. 247 Müll.: polubrum quod Graeci χέρνιβα, nos trulleum vocamus. Livius: argenteo polubro (acc. to Hom. Od. 1, 136); Fabius Pictor, lib. xvi.: polubrum sinistrā manu teneto, Non. 544, 22 sq.