Here's what rhymes with thingyness.
                        
                        
                    
                                Words that almost rhyme with thingyness
griminess  fierceness  siliceous  filminess  willingness  impishness  skittishness  piggishness  spirituous  spiritless  priggishness  derisiveness  certificates  precipitous  litigants  iniquitous  permissiveness  submissiveness  indigents  cliquishness  jinrickshas  jinrikshas  significance  coincidence  ubiquitous  distinctiveness  vindictiveness  explicitness  duplicitous  implicitness  restrictiveness  serendipitous  descriptiveness  insignificance