Mississippi & Tennessee
bookkeeper
3. Actually, it is the only English word with 3 sets of double letters in a row.
The English word BOOKKEEPING or BOOKKEEPER has three sets of consecutive double letters. SUBBOOKKEEPER is the only word with four sets of consecutive double letters, although these words should be hyphenated.
Mississippi
The only one I can think of is bookkeeper. Are there others?
Mississippi & Tennessee
Mississippi
Well, there's probably more than three. Right now I could only think of "balloon" and raccoon though, assuming that you meant those double letters have to be next to each other.
Bookkeeper
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