Mammoth Uncensored Word List:
23 - 19 letter words starting with h

hemangiopericytomas hemidemisemiquavers hepaticojejunostomy heterogeneousnesses histopathologically historiographically holoprosencephalous homotransplantation hydrochlorothiazide hydrometeorological hydrometeorologists hyperconcentrations hyperdolichocephaly hyperemotionalities hyperexcitabilities hyperirritabilities hyperparathyroidism hypersensitizations hypersophistication hypersusceptibility hypoadrenocorticism hypocholesterolemia hypoparathyroidisms