Is 'bookkeeper' the only English word with three consecutive repeated letters?
It isn't the only word of this kind, but it's the only one in which removing the hyphen and merging the two words is a practical option. If you took the hyphens out of words like hoof-footed or sweet-toothed, for example, you'd be left with the off-putting and fairly unrecognizable forms hooffooted and sweettoothed.
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