From un- + bumptious. <span class="searchmatch">unbumptious</span> (comparative more <span class="searchmatch">unbumptious</span>, superlative most <span class="searchmatch">unbumptious</span>) Not bumptious....
a lightning mixture of black and white murder that the eye could not follow it. bumptiously bumptiousness overbumptious <span class="searchmatch">unbumptious</span> obtrusively pushy...