Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
pānārĭum (pann-), ii, n. [panis], a bread-basket: hinc panarium, ubi id (sc. panem) servabant, sicut granarium, ubi granum frumenti condebant, unde id dictum, Varr. L. L. 5, § 105 Müll.; Plin. Ep. 1, 6, 3; Suet. Calig. 18; Stat. S. 1, 6, 31.