noun, noun which may take the genitive case particle 'no'
horseback riding; mounted
Refers to riding a horse or being on horseback. Often used attributively (騎馬の) to describe things related to mounted activity, such as 騎馬隊 (mounted troops) or 騎馬戦 (cavalry battle). The gloss 'horseback rider' is a contextual extension, not a separate sense.
彼は騎馬で草原を駆け抜けた。
He galloped across the plain on horseback.
騎馬警官がパレードを先導した。
Mounted police officers led the parade.