Some six letter words with the fourth letter U are:
ACROBATIC that is the word i found in the top of my head(: 9 letters, O for the 4th...helpful? (:
bladders
ballroomballgamebafflingbattlingbillablebillfoldbloomingbutteredcommutercommentscommandocollapsecollagencarriagecurrencycommonlydifferedhammeredfreebornfreebasefreehandfreeloadhorriblygreenerygroomingfloodlithappenedjudderedmarriagepepperedsleepingsnoopingscoopingspeedingsufferedsuddenlysuggestssuppliedsupportssupposedsuppresssurroundsweepingtrammels
Buzzing
butterfly
soldier
ACROBATIC that is the word i found in the top of my head(: 9 letters, O for the 4th...helpful? (:
bladders
There is no 9 letter word, 4th letter r that can be made from those letters.
ballroomballgamebafflingbattlingbillablebillfoldbloomingbutteredcommutercommentscommandocollapsecollagencarriagecurrencycommonlydifferedhammeredfreebornfreebasefreehandfreeloadhorriblygreenerygroomingfloodlithappenedjudderedmarriagepepperedsleepingsnoopingscoopingspeedingsufferedsuddenlysuggestssuppliedsupportssupposedsuppresssurroundsweepingtrammels
proof
Buzzing
butterfly
kumala or kumata
human
dividing
reversed