equestrian

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Of or relating to horseback riding or horseback riders.
2. adj. Depicted or represented on horseback: an equestrian statue of a famous monarch.
3. n. One who rides a horse or performs on horseback.

Century Dictionary and Cyclopedia

1. Pertaining or relating to horses or horsemanship; concerned with horses or riding; consisting in or accompanied with performances on horseback: as, a person of equestrian tastes; an equestrian picture; equestrian feats, exercise, or sports.
2. Riding or represented as riding on a horse; exercising or mounted on horseback: as, equestrian performers; an equestrian statue of Washington. Equestrian statues are usually cast in bronze and mounted on a stone pedestal. Few early monuments of this kind are extant, the valuable metal they contained tempting ravagers to destroy them.
3. Of or pertaining to the Roman equites or knights: as, the equestrian order. See equites.
4. n. A rider on horseback; specifically, one who earns his living by performing feats of agility and skill on horseback in a circus.

Wiktionary

1. adj. of horseback riding or horseback riders
2. n. an equestrian person; a horserider

GNU Webster's 1913

1. adj. Of or pertaining to horses or horsemen, or to horsemanship.
2. adj. Being or riding on horseback; mounted.
3. adj. Belonging to, or composed of, the ancient Roman equities or knights.
4. n. One who rides on horseback; a horseman; a rider.

WordNet 3.0

1. n. a man skilled in equitation
2. adj. of or relating to or featuring horseback riding
3. adj. of or relating to or composed of knights