Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
ŏpercŭlo, āvi, ātum, 1, v. a. [operculum], to furnish or cover with a lid, to cover (post-Aug.): dolia, Col. 12, 30, 1: vasa, id. 12, 15, 2: operculati favi, id. 11, 2, 50; 57.