Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
nūbĭlis, e, adj. [nubo], marriageable: filia, Cic. Clu. 5, 11: virgo, Liv. 29, 13: jam plenis nubilis annis, Verg. A. 7, 53: nubiles anni, Ov. M. 14, 335.