Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
‡ strătĭo, ōnis, f. [sterno], the laying of cloths and coverings, the preparation of a room for a feast, Inscr. Fabr. 404, 306; Inser. Att. Ac. Rom. Archaeol. 2, 462.