Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† prŏnāus or -os, i, m., = πρόναος, the porch, vestibule, portico of a temple, Vitr. 3, 1 fin.; 4, 4, 1; 4, 7, 2; 5, 1, 9; Inscr. Grut. 27, 2; 214.