Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
‡ plĕo, ēre, v. n., to fill, to fulfil, the root of plenus, q. v., compleo, expleo, suppleo: plentur antiqui etiam sine praepositionibus dicebant, Fest. p. 230 Müll.