1. the sport or activity of racing horses, typically with jockeys riding them
Usage: often used as a mass noun (uncountable); can also be written as 'horse racing' (two words)

Examples

• Horseracing is a popular sport with a long history in many countries.
• She has been interested in horseracing since she was a child.
• The Kentucky Derby is one of the most famous horseracing events in the world.
• He made a fortune betting on horseracing.
• Horseracing requires skilled jockeys and well-trained thoroughbreds.
• The horseracing industry employs thousands of people.