What does ‘a dark horse’ mean?

To “a dark horse” means to a competitor whose abilities are unknown until they prove strong. Brewer's records this as a turf term: a horse whose form has been kept secret to lengthen its odds. Popularized by Disraeli's novel The Young Duke (1831).

Origin

  • Brewer's records this as a turf term: a horse whose form has been kept secret to lengthen its odds. Popularized by Disraeli's novel The Young Duke (1831).

How to use it

  • Used in politics and sports for surprise contenders.
  • Example: The new candidate is a dark horse in the race.

Source:

Last verified: 2026-07-18

  • Definitions and origins are drawn from public-domain reference works, primarily Brewer's Dictionary of Phrase and Fable (1898), with modern usage notes clearly marked.

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