What Is the Meaning of 'Dark Horse'?

A dark horse isn't just black or brown. The meaning of the English idiom dark horse comes from a different meaning of dark.

Samantha Enslen, Writing for
2-minute read

dark horse meaning

The 2015 Kentucky Derby is coming up soon. If you’re rooting for Bolo or Ocho Ocho Ocho, you’re betting on a dark horse. Literally and figuratively.

These two ponies are dark bay colts. That means their bodies are a deep brownish red. Their manes, tails, and legs are black. They’re literally “dark horses.” 

They also have a slim chance of winning. Two days before the Derby, Bolo's odds are listed at 30 to 1. Poor Ocho's are only 50 to 1.

Bolo and Ocho are figuratively dark horses, too. They’re contestants barely known by the public. Remember that in addition to meaning dark in color, dark can also mean “unknown, hidden, or secret.”

As you might have guessed, the term “dark horse” comes from horse racing. It was first recorded in 1831 in a book by Benjamin Disraeli. He describes how “a dark horse, which had never been thought of…rushed past the grand stand in sweeping triumph.”

The term soon jumped from racing to politics, where it was used to describe a little-known candidate who comes from behind to unexpectedly win a race. 

For example, an 1893 Wall Street Journal article described the Democratic national convention like this. “Bryan broke loose too soon…Bland’s strength will wane after the first ballot. It will then be anybody's race. Cool-headed leaders say the convention may last over Sunday barring a stampede for a dark horse.”

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. 

So here’s your tidbit for the day: the term dark horse means “an underdog or unlikely winner.” 

Samantha Enslen runs Dragonfly Editorial. You can find her at dragonflyeditorial.com or on Twitter as @DragonflyEdit.


2015 Derby Contenders. Kentucky Derby. www.kentuckyderby.com/horses (accessed April 13, 2015).

Ammer, Christine. Dark Horse. American Heritage Dictionary of Idioms, 2nd ed. Houghton Mifflin Harcourt, 2013. http://bit.ly/1H4FrZ4 (accessed April 13, 2015).

Bay Horse Coat Color Modifier. The Equinest. http://bit.ly/1PJ9qd8 (accessed April 13, 2015). 

Chicago Special. The Wall Street Journal, July 10, 1896. http://on.wsj.com/1b0y2yd (accessed April 13, 2015).

“dark.” Oxford English Dictionary, online. http://0-www.oed.com.innopac.library.unr.edu/view/Entry/47295 (subscription required, accessed April 26, 2015).

Image courtesy of Shutterstock.

About the Author

Samantha Enslen, Writing for Grammar Girl

Samantha Enslen is an award-winning writer who has worked in publishing for more than 20 years. She runs Dragonfly Editorial, an agency that provides copywriting, editing, and design for scientific, medical, technical, and corporate materials. Sam is the vice president of ACES, The Society for Editing, and is the managing editor of Tracking Changes, ACES' quarterly journal.