Mammoth Uncensored Word List:
64 words ending with es, 20 letters long

anthropocentricities chlorofluoromethanes comprehensiblenesses counterintelligences countersurveillances countertransferences deoxyribonucleotides dimethylnitrosamines distinguishabilities electroluminescences electrooculographies electrophotographies expressionlessnesses extemporaneousnesses forethoughtfulnesses gastroduodenostomies glomerulonephritides glycosyltransferases histocompatibilities hydrochlorothiazides hypercoagulabilities hyperconsciousnesses hypersensitivenesses inappreciativenesses incommensurabilities inconsequentialities inconsiderablenesses indestructiblenesses indiscriminatenesses interchangeabilities interconnectednesses irreconcilablenesses irreproachablenesses keratoconjunctivites lymphogranulomatoses lymphoscintigraphies microcrystallinities microelectrophoreses nephroureterectomies neuroendocrinologies nondestructivenesses overintellectualizes overprotectivenesses pachycephalosauruses paradichlorobenzenes phenylpropanolamines phenylthiocarbamides phosphatidylcholines phosphoenolpyruvates phosphofructokinases phosphomonoesterases photoreconnaissances psychopharmacologies representativenesses sigmoidorectostomies spectrofluorometries spectroheliographies tracheolaryngotomies ultrarevolutionaries uncompromisingnesses unconscionablenesses unintelligiblenesses unsatisfactorinesses vasoepididymostomies