Bookkeeper. Although Subbookkeeper has four.
The following words have three consecutive sets of double letters:bookkeeperbookkeepersbookkeeping
3. Actually, it is the only English word with 3 sets of double letters in a row.
Mississippi
committee
bookkeeper
bookkeeper
bookkeeper, bookkeeping
Mississippi
bookkeeping
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.
No words were found in the English dictionary. The name Exxon has a double x. Exxon is a brand of petroleum based products manufacturered by the ExxonMobil company.
Clicking Twice in quick succession.