Danny Kelly has said he's absolutely delighted that Boris Johnson has used the word mugwump - because it's brought the word back.
The foreign secretary used the term to describe Jeremy Corbyn, as he suggested the Labour leader poses a threat to the country.
Many people claimed the term originated from a Roald Dahl book, or from Harry Potter. But Danny says this isn't the case.
In fact, he says, the word was actually first used by a US cartoonist in the 19th century, to describe Republicans who had started to vote for the Democrats.
He then said that it was later used in the book Naked Lunch by William S Burroughs to describe an unrecognisable creature.
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