Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
* vĭbĭa, ae, f., a plank, cross-piece supported on trestles (varae) so as to form a bank; hence the proverb: sequitur varam vibia, one error follows another, Aus. Idyll. 12 praef. monos.; v. vara.