A maiden race is a race for horses that have not previously won. They are held over a variety of distances and conditions with the right to run based on the sex or age of the horse.
Flat and Jump racing are treated as two different forms of racing; a horse that has won Jump races is still eligible to run in maiden races on the Flat, as long as they have not won on the Flat. Likewise, Flat race winners are eligible to enter hurdle or chase maidens if they have not won the relevant type of Jump race.
A maiden horse remains a maiden until it wins a race. That sounds pretty simple. The horse may take only a couple of races before it bursts from the pack and crosses the line first. Or, it could be years until a horse finally claims victory and enjoys the celebrations its peers have long-since got used to.
- Maiden races tend to be contested by horses at the start of their racing career.