Meaning
A competitor or candidate who is little known but unexpectedly achieves success, or whose abilities are hard to judge because so little is known about them. Common in politics, sport, and competitions. Neutral to admiring; often used in predictions and commentary on contests. Regional use: General English.
Origin
The phrase began as British horse-racing and betting jargon for a racehorse whose form was unknown to gamblers, making the odds hard to set. The earliest known reference is in Benjamin Disraeli's novel The Young Duke (1831), describing a race won by 'a dark horse, which had never been thought of'. Figurative use outside racing followed within decades: The Saturday Review used it in 1860 of an academic appointment won by a man who had 'judiciously kept himself dark', and Sketches from Cambridge (1865) remarked that 'every now and then a dark horse is heard of'. The metaphor relies on 'dark' simply meaning hidden or obscure, and no competing origin theory is recorded.
Research Sources
References used to check this entry’s meaning, history, or documented forms.
Variants
- a dark-horse candidate
- dark horse in the race
- dark horses
Usage Examples
- Few had heard of the young midfielder before the tournament, making her team a genuine dark horse.
- Party elders began treating the junior senator as a dark horse for the leadership contest.
- The startup was a dark horse at the demo day until its live prototype silenced the room.