In the meantime, if you run across something in one of my books that's got you scratching your head, post your question in the comments and I'll be happy to explain. Or at least try.
Average - Usually used to describe the aggregate score for a contestant who competed in more than one round, e.g., “He had times of 9.3 and 9.8 seconds in the two rounds and placed third in the average with 19.1 seconds on two head”
Bareback Riding - The favored event of the Sanchez brothers in the Texas Rodeo books, the cowboy rides the bucking horse with only a 'rigging' strapped to the animal's withers: https://www.youtube.com/watch?v=jgxbDbdW3UE
Barrelman - An entertainer who uses a barrel to distract a bull after a ride, and sometimes to protect the cowboy.
Barrier - In timed events, a line at the front of the box that the contestant and his horse cannot cross until the steer or calf has a head start, usually marked with a rope and a flag so the timers can see it drop and start the clock
Box - In a timed event, the area a horse and rider back into before they make a roping or steer wrestling run
Breaking the barrier: in the timed events, if the rider leaves the box too soon – failing to give the animal enough of a head start – he is assessed a 10-second penalty.
Breakaway Roping - My number one event and the most popular women's version of calf roping. The goal is to catch the calf as quickly as possible then stop your horse, allowing the string attaching the rope to the saddle horn to 'breakaway', thus the name of the event. https://www.youtube.com/watch?v=R8YNP6oDi7U
Bronc Rein - A saddle bronc rider holds onto a bronc rein at a specific position that he determines based on the size and bucking habits of the horse he’s about to ride; bronc riders often give each other advice about the length of rein a specific horse will perform best with, e.g., “Give him 3½ fingers”
Bulldogger - A steer wrestler
Bullfighter - An athlete who protects the bull rider after he dismounts or is bucked off by distracting the bull and directing its attention to the exit gate, sometimes stepping between the bull and the bull rider. For an inside the arena look: https://www.youtube.com/watch?v=X-x8cbIxNtQ
Calf roper - A tie-down roper
Chute - A pen that holds an animal safely in position
Circuit - Rodeo is an incredibly complex sport that happens at many, many different levels: Pee Wee, Junior, Junior High, High School, College, Senior Pro (40+). There are full-time competitors for whom it is their livelihood and there are people who have regular jobs and compete whenever they can, generally within their geographical region, and cowboys and cowgirls who fall everywhere on the spectrum in between. There are state and regional associations that are not affiliated with the Pro Rodeo Cowboys Association, and then there are what is commonly referred to as the 'circuits', which are (example: Texas Circuit, Montana Circuit, Badlands Circuit). I'll let them explain it to you: http://www.prorodeo.com/news-display/2018/04/04/rncfr-then-and-now
Covering: in the roughstock events, staying on for at least the minimum time, eight seconds: “He covered all three broncs he rode last weekend.”
Crossfire penalty - In team roping, if the header doesn’t change the direction of the steer before the heeler catches, the run is disqualified
Dally - In team roping, each roper, after throwing his loop, wraps the loose rope around his saddle horn – dallies – and the two ropers move their horses to face each other, pulling the ropes taut to stop the clock.
Drop - In roughstock events, the way a bucking horse or bull may lower its front end suddenly while kicking out in back, creating a more difficult ride; in timed events, the way a calf or steer may lower its head to avoid a catch.
Flankman - A cowboy or cowgirl who works in the bucking chutes, adjusting the flank strap around the animal before the ride; the best flankmen and women are familiar with each individual animal and know exactly how much flank to give each animal to encourage optimal bucking.
Flank strap - A soft sheepskin- or Neoprene-lined strap placed in the area where a human’s belt would go, it encourages the animal to kick out behind itself rather than rear up, which provides a safer, showier ride.
Go-round - Many rodeos have more than one round of competition; each is called a go-round, and all cowboys entered in that rodeo compete in each go-round unless there is a semi-final, final or progressive round.
Hazer - In steer wrestling, the cowboy who rides on the right side of the steer from the contestant to make sure the steer runs straight.
Header/Heeler - The two partners in team roping – the header throws the first rope, over the animal’s head or horns, and the heeler throws the second rope to catch both the steer’s hind legs; roping one leg results in a five-second penalty.
Hooey - The knot that a cowboy uses to finish tying the calf’s legs together in tie-down roping.
Hung up - When a bull rider or bareback rider cannot remove his hand from the rope or handle before he dismounts or is thrown off the bull’s or horse’s back, his hand is “hung up” – a dangerous situation – and the pickup men or bullfighters will move in to help dislodge his hand so he can get clear of the animal. Here's a great look at the bullfighters at work: https://www.youtube.com/watch?v=IeZV3EoWegA . And here are the pickup men making a great save: https://www.youtube.com/watch?v=NaLv32eZ4Fs
Left (or right) delivery - Many bucking animals prefer to stand in the chute facing a particular direction, so they can leave the chute in the direction they prefer.
Mark out - In the bareback and saddle bronc riding, a cowboy’s feet must be above the point of the horse’s shoulders when the horse’s front feet hit the ground – if so, he “marked the horse out,” but if not, he “missed him out” and the ride is disqualified.
Permit holder - A PRCA contestant who has not yet won his first $1,000 at PRCA rodeos, which enables him to apply to become a card-holding member of the organization
Pickup men - Two mounted cowboys who help riders dismount, release a bucking horse’s soft flank strap, and escort bucking horses and bulls to the exit gate after a ride. Or, yes, cowGIRL: https://www.youtube.com/watch?v=0FMiMoenlKU
Piggin’ string - In tie-down roping, the small rope used to tie a calf’s legs together.
Pigtail - A piece of string attached to the barrier that breaks if a timed-event contestant’s horse exits the box too soon, not giving the calf or steer enough of a head start according to PRCA rules.
Reride - If a cowboy’s score is affected by equipment failure or a horse or bull that doesn’t buck to performance specifications, the judges may offer the cowboy a clean-slate chance on a different horse or bull.
Riggin’ - A suitcase-style handhold customized to a rider’s grip and attached to a molded piece of leather that is cinched, with a pad, around the horse’s girth.
Ropes - The correct term is rope, not lasso, lariat or riata; most ropes used in ProRodeo timed events are made of strong yet flexible braided materials such as nylon/poly blends, and a cowboy may change his rope selection depending on the weather and the cattle; bull ropes and bronc reins are often made of sisal or poly blends.
Roughstock - The bucking horses and bulls used in bareback riding, saddle bronc riding and bull riding, usually bred and raised for the job.
Slack - Excess entries at some rodeos may be scheduled for preliminary (slack) competition, usually before the rodeo opens to the public.
Spur Board - a contraption especially popular with bareback riders for practicing and strengthening their spurring motion. The one Gil and Delon Sanchez have in their shop looks something like this: https://www.tennessean.com/story/news/local/williamson/2017/05/16/man-vs-beast-night-franklin-rodeo/314625001/
Spurs - The spurs used in PRCA rodeos have dulled rowels that do not penetrate the animals’ skin, which is several times thicker than human skin
Stock contractors - The companies that bring livestock to the arena for rodeos – bucking horses and bulls for the roughstock events and steers and calves for the timed events. Take a peek behind the scenes with the Calgary Stampede string: https://www.youtube.com/watch?v=W2M-HhLjfeQ
Team Roping - An event in which the 'header' ropes the steer by the horns, then the 'heeler' attempts to catch both feet. Catching a single foot results in a five-second penalty. This is the event favored by most of the women in my Texas Rodeo books. https://www.youtube.com/watch?v=pbcoyDMDSWQ
Triple Crown winner - A cowboy who wins three world championships in the same year; the most recent cowboy to do so was superstar Trevor Brazile in 2008 and 2010.
Try - A noun used for both cowboys and livestock, denoting grit, determination, fitness, stamina and resilience: “Give that cowboy a hand – he had a lot of try.”
Turn out - A cowboy may turn out of a rodeo if, for example, he has a scheduling conflict; this is different from “doctor-releasing” due to injury.