I only know of one
Vacuum
1,000 to 3,000
There is no double letter word with the letter x
scoopscootshootsheetsheepsheersloopspoonspoolsleeksleepsnoopsteepstoopsteersweepsweetswoop
none
killkeepkangarookazoo
6-letter wordssayyid7-letter wordssayyids2 words found.
addassallillofferrbeeseefeepeeteeweezooboocoogoomootoooddebb
abbreviatebabblebubbleblubbercabbagecribbagechubbycrabbydabbledribbleebbflabbygabbygibbetgibberishgobblehobblejabberlobbynibblepebblequibblerabbitrubbishrubblestubbletabbedtabbytubbywobble
Ill and inn.
sully, sunny
Because every language in the world has its own rules for its alphabet. In many languages, double letters are just not necessary.
Some six letter words that end in double letters:accessacrossapogeebamboobefallboo booboohoobungeebypasscaresscoffeecouleecuckoodecreedegreeduressegressembossenrollentreeexcessgoateeharassHawaiilayofflycheemorassmuumuupayoffpeeweepizazzrebuffrecallrecessrefillremissripoffrunoffscrollscruffsetteeshrillsoireesquallstressstrolltarifftattoothrilltoffeetoupeeunlessvoodoo