A separate skirt fastened around the waist over the other dress, worn by women in riding.(noun)
The Century Dictionary (Public Domain)
Use "riding-skirt" in a sentence
"She leaned forward under the flying steel, which cut through her riding-skirt, through the edge of the saddle, through the saddle cloth, and even slightly into the horse itself."
"The exquisite feminine beauty of her countenance, now shaded only by a profusion of sunny tresses; the sylph-like form, disencumbered of her heavy riding-skirt and mantled in azure silk; the grace of her manner and of her smile, cleared, with a celerity which surprised the Master himself, all the gloomy and unfavourable thoughts which had for some time overclouded his fancy."
"I wish she would lift up that lang veil, or put off that riding-skirt, Doctor."