Free Drop Billy. Lone Sailor. Good Magic. Instilled Regard.
If you guessed those were the names of some of the horses competing in this year’s Kentucky Derby, you’d be right. If you also thought that those words seem like they belong in a game of Mad Libs, you wouldn’t be wrong. That’s because officially naming a thoroughbred comes with some interesting limitations.
The names of the Kentucky Derby contenders are often the highlight of the competition. And if you’ve ever wondered how the heck someone came up with a horse name like that, then you’re in luck. We’re here to provide some background.
The Kentucky Derby is reserved for 3-year-old thoroughbreds. The Jockey Club, the breed registry for thoroughbred horses in the United States, Canada and Puerto Rico, is the organization responsible for approving thoroughbred names.
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Although owners can get creative with their selection, it’s common to name a horse after its pedigree, including something involving the name of the horse’s dam (female parent), sire (male parent) or a combination of the names. Some owners also turn to favorite pastimes or words as well as pop culture for inspiration.
Then, there are the rules.
As stated on the Jockey Club site, names aren’t eligible if they are more than 18 letters (the Jockey Club seems to work like Twitter, as spaces and punctuation count as letters) or are made up of only initials or only numbers (if you want to use a number above 30, it has to be spelled out, which might make you max out your character limit). Names also can’t end in “filly,” “colt,” “stud,” “mare,” “stallion” or related terms.
As for jockeys who also might be pop culture junkies, the Jockey Club won’t approve names of living people unless it has written permission. It won’t accept names of those who have died “unless approval is granted by The Jockey Club based upon a satisfactory written explanation submitted to the Registrar.” In addition, names “clearly having commercial, artistic or creative significance” won’t get you anywhere (think movies, songs, etc.).
In a more obvious rule, the Jockey Club will not give the OK for names with “vulgar or obscene meaning” or names that could be offensive “to religious, political or ethnic groups.” In 2007, Slate revealed that some scandalous names (like On Your Knees) had made it to the registry, and Rick Bailey, registrar of the Jockey Club, admitted some “questionable names might have slipped by” because of the high number of submissions.
Did we mention names already in use are out of the picture? The Jockey Club does regularly put out a list of “released” names, though, or names from horses more than 10 years old that haven’t been used for breeding or racing in the last five years. In December 2017, the Jockey Club released 42,659 names.
These are just a handful of the rules. There are more guidelines about referencing racetracks in names and trying to give your horse what the Jockey Club considers a “permanent name,” typically designated for horses who win major races or large financial prizes. If the Jockey Club rejects a name, the most common reason is because it’s already been taken.
The names might not seem to make sense on the surface, but there are fun stories about the Kentucky Derby horses’ names every year. Aside from horses like Magnum Moon and Good Magic that have names associated with their pedigree, there’s also Bolt D’Oro, a nod to Olympic champion Usain Bolt. Audible’s name was inspired by a tactic used in football, according to the Lexington Herald Leader, and the name Free Drop Billy is rooted in the horse owner’s friend taking frequent free drops (penalty-less moves) while playing golf.
You can thank the owners and their creativity for these fun mini histories ― and the several rules they have to follow, of course.
This article originally appeared on HuffPost.