There are two such words:
irresponsibility
and
apprehensiveness
attentiveness
Bookkeeper
addseggsoddsAnnebeefbeenbeepbeerbeetbootbookboomboonbooscoolcootdeerdeepdeeddeemdoordoomfeedfeelfeetfoodfoolfootgoodgeedgoofgoongoopheedheelheedhoodhoofhoophootjeepjeerkeepkeelkeenleekleerloonloomlooplootmeetmoodmoonmoormootneednooknoonpeerpoofpeelpoolpeeppeerroofroomrootreedreelseedseemseenseerseessoonteentooltootwoolweedwoodwoofweep
boxtops
benefitsfanaticalfinishedgeneralsgenerategeneroushonoraryminicampmonogamymonogrammonoxidemonorailrenegaderenewalssinistertenementvenerate
dividing
reversed
array
4 letter words, letters 2 and 3 are the same:allybeetbeenbeefbeepbeerbeesboomboonbootcookcoolcoopdeepdeeddeerdoomdoorfeedfeelfeesfeetfoodfoolfootgoodheelhoodhoofhoophootjeepkeepleerloomloonlooplootmeetmoodmoonseedeggsElla
pemmican
believed, believes, believer, relieved, relieves, reliever, helmeted
Four_letter_words_that_have_the_same_letter_for_the_first_and_third
Pepper