Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† ornīthon, ōnis, m., = ὀρνιθών, a birdhouse, poultry-house (pure Lat. aviarium): ornithonas dico omnium alitum, quae intra parietes villae solent pasci, Varr. R. R. 3, 3, 1; 3, 4, 2; Col. 8, 3, 1.