Undoubtably? Doubtable

In his latest column ("Inaugural II: This time it's personal"), Will Durst was not only hilarious as usual, but inventive—he coined a new word:

"...more fiber is undoubtably a good thing."

Strangely, "undoubtable" is in the dictionary but "undoubtably" isn't. The word Mr. Durst may have meant to use (unless he was just being creative) was "undoubtedly."

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