Mammoth Uncensored Word List:
70 - 13 letter words starting with do

dociblenesses doctrinairism doctrinarians doctrinarisms documentalist documentarian documentaries documentarily documentarise documentarist documentarize documentation dodecahedrane dodecahedrons dodecaphonies dodecaphonism dodecaphonist doggishnesses dogmatisation dogmatization dogmatologies dolefulnesses dolichocephal dolichosaurus dollarisation dollarization dollishnesses dolomizations dolorimetries dolphinariums dolphinfishes doltishnesses domesticating domestication domesticative domesticators domesticising domesticities domesticizing domiciliating domiciliation domineeringly donnishnesses doomwatchings doorsteppings doppelgangers dorsalization dorsiflexions dosedependent dosimetrician doublechecked doublecrossed doublecrosses doubledealers doubledealing doubledeckers doubleheaders doublehelical doublespeaker doubtlessness doughnuttings doughtinesses doveishnesses downheartedly downloadables downregulated downregulates downrightness downshiftings doxologically