From un- + drooping. <span class="searchmatch">undrooping</span> (comparative more <span class="searchmatch">undrooping</span>, superlative most <span class="searchmatch">undrooping</span>) Not drooping. 1851, Sam G. Goodrich, Poems[1]: A good deed...
something drooping. drooping (comparative more drooping, superlative most drooping) That droops or droop. drooping flowers droopingly droopingness <span class="searchmatch">undrooping</span>...