Obstacle Course Racing — an event requiring an athlete to run through a variety of different obstacles.
Offroad Boarding — another name for Mountainboarding
Off-Road Racing — many motor sports have competitions 'off-road', meaning on rough terrain.
Oil Wrestling — a form of wrestling called Yağlı Güreş in Turkey, is where the wrestlers cover themselves in oil.
Oină – a Romanian traditional sport, similar in many ways to Baseball and Lapta played outdoors by two teams of 11 players, taking turns either batting or catching.
Okinawan Kobudō — weapon systems of Okinawan Martial Arts, also known as Ryūkyū Kobujutsu.
One Day International (ODI) — a form of Cricket played in a single day, usually 50 overs per team. An even shorter version is the Twenty20.
open water (ocean) swimmingopen water (ocean) swimming
One-Pocket — a version of Pocket Billiards where the objective is to pocket all the object balls into a single pocket.
Open Water Swimming — competitive swimming races conducted over various distances (10km at the Olympics) held in rivers, lakes and oceans.
Orienteering — participants find their way to various checkpoints across rough country with the aid of a map and compass, the winner being the one with the lowest elapsed time.
Outdoor Handball — another name for Field Handball.
Outrigger Canoeing — racing using a type of canoe featuring one or more lateral support floats known as outriggers, which are fastened to one or both sides of the main hull.
Over-the-line – a bat-and-ball sport related to baseball and softball with just 3 people per team. Unlike the other sports, the batter and pitcher are on the same team.
I've poured enough drinks to know that people don't always want advice—they just want to talk.
Chat with Devin
Maxine
I respect you enough to keep it real.
Chat with Maxine
Coach
Success isn't just about winning—it's about vision, patience, and playing the long game.
Chat with Coach
More answers
Here are a few I have found: Off-Road Multisport, Offroad
Vehicles, Offshore Boat Racing, Olympic Lifting, Open Water
Swimming, Orienteering, Outrigger, Off-Road Skating, Outdoor
Sports, Outdoor Camping, Open Fishing.