dark horse
noun phrase

1. One who achieves unexpected support and success as a political candidate (typically during a party’s convention)

2. A little-known, unexpectedly successful entrant, as in a horserace.

The American Heritage Dictionary of the English Language

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ORIGIN

This idiom is said to go back to the Victorian politician Benjamin Disraeli who, apart from finding time to regularly become Prime Minister, also found time to write a novel called “The Young Duke”. In the book there is a description of a horse race in which the two favourites cannot make the running. In the meanwhile “a dark horse…rushed past the grandstand in a sweeping triumph”.

The phrase is still used today. In a 2013 pop song, Katy Perry asks, “Do you dare to do this? ’Cause I’m coming at you like a dark horse.” Who knows what rock stars really mean in their lyrics, but we can guess that Perry meant she was an unexpected suitor who would be unexpectedly successful.

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SYNONYMS

an unlikely winner, a long shot, a hundred-to-one shot, a slim chance, an (a complete) unknown

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Practice OWAD in a conversation, say something like:

“Jim is a bit of a DARK HORSE, no-one expected him to be promoted to the board so quickly.”

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