Some people maintain that "rhythms" qualifies. I don't.
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Inimical comes to mind, but I'm sure there are others. I can do you one letter better: a 7 letter word that contains three Is is "idiotic".
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The word Mollusk is a 7 letter word.
bombast
squeals
zygotes
success
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effaced, efforts, effects
algebraarrestsascendsbenefitboredombreederbreezescarefulcateredcheesescheereddeceivedefencedemeritdeservedetestsdevelopdigestsdinettediverseexpectsexpanseexpenseexpertsextendsforeignforestsforeverfriendsfreedomfreewaygreetedimpedesinheritintenseinventsinversemementomiserlyoffencepageboyparentspovertypreemptreceiverepentsreleaserepealsrevealsresealsreverseselectssleevessneezessomedaysteeplesteeredstretchtalentsthreads
bellhop
abdomen
Some people maintain that "rhythms" qualifies. I don't.
therein
The only American English word that contains those letters is AZURE; there are no 6 or 7 letter words.