From under- + improved. <span class="searchmatch">underimproved</span> (not comparable) Having undergone insufficient improvement. an <span class="searchmatch">underimproved</span> office building...
said NR's Wessex Route Director Mark Killick. nonimproved overimproved <span class="searchmatch">underimproved</span> unimproved that has been made better improved simple past and past participle...