Dark Horse 

A song (a great one too, although not terribly well sung or produced) and the title track of the 1974 Apple album of the same name by the late, great George Harrison. Dark Horse was also the name of the visionary guitarist and composer's record label (distributed by the Brothers Warner), which he recorded seven albums for after leaving Apple (the label the Beatles formed in 1968) in 1976. Harrison himself was also known as the Dark Horse of the Beatles, a reference to a racehorse that people bet little on in the beginning, but who ultimately outshines his competitors in the end. When you have Lennon, McCartney and Martin as your mentors and Clapton, Dylan, and Shankar as three of your best friends, you can't help but radiate brilliance, as George did — and still does. As the Man himself sang:

"I'm a dark horse
Running on a dark race course
I'm a blue moon
Since I stepped out of the womb
I've been a cool jerk
Looking for the source
I'm a dark horse."

Dark Horse by Victor Felix October 1, 2005

dark horse 

a secret male slut who no one excepts to be a womanizer

Mrs. Burgess upon seeing tom's pencil case "Tom your a dark horse"

dark horse by Jess January 3, 2005

Dark Horse 

Used to describe a black man with an abnormally large penis; frequently compared to the size of a horse's cock>

"YO Tanisha, I had no idea Devonte was a Dark Horse! Imean i really wasn't ready for that>"

Dark Horse by SessyPuertoricanPimpo September 1, 2016

Dark Horse 

An lovable, athletic and intelligent creature!

Wow, Jacob is such a dark horse :)

Dark Horse by hhhu November 18, 2019

Dark horse 

An organism you make with you hand when u feel attacked. It is made as you fold you fingers on top of each other one by one. VERY SCARY.

"Your so stupid"
Im sending my dark horse after you.

Dark horse by GRAAAH March 19, 2024

Dark Horse Security Inc.

A fake cyber-security business created by Alameen Karim Merali as the CFO that runs with his alter ego Madeline Escobar as the CEO, whose actually a porn star.

The business Dark Horse Security Inc. has seen success in the cyber-security world regardless of it being fake, and is in the news.

Dark Horse Security Inc. by Cat Hat Ethical November 5, 2023

Dark horse days 

The dark days aren't over, and they're not going to be without a fight. Things are going to keep getting shut down unless people wake up and fight.

The dark horse days are not something people get to forget yet, since they are not over yet, as people are told they are in some countries.

Dark horse days by Solid Mantis January 4, 2021