Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
excĭpŭla, ōrum (sc. vasa), n. [excipio], vessels for receiving liquids, receivers, receptacles, Plin. 25, 7, 38, § 78: in excipulis ejus fluminis, i. e. cavities, basins, id. 9, 22, 38, § 75.