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