Emily Dickinson Lexicon

E-QUES'TRI-AN, a. [L. equester, equestris, from eques, a horseman, from equus, a horse.]

1. Pertaining to horses or horsemanship; performed with horses; as, equestrian feats.
2. Being on horseback; as, an equestrian lady. Spectator.
3. Skilled in horsemanship.
4. Representing a person on horseback; as, an equestrian statue.
5. Celebrated by horse-races; as, equestrian games, sports, or amusements.
6. Belonging to knights. Among the Romans, the equestrian order, was the order of knights, equites; also their troopers or horsemen in the field. In civil life, the knights stood contra-distinguished from the senators; in the field, from the infantry. Encyc.