"pertaining to or relating to horses or horsemanship," 1650s, formed in English from Latin equester (genitive equestris) "of a horseman, knightly," from eques "horseman, knight," from equus "horse" (from PIE root *ekwo- "horse"). As a noun, "one who rides on horseback," from 1786. The feminine form equestrienne is attested from 1848 (Century Dictionary calls it "circus-bill French"). An earlier adjective was equestrial (1550s).
)window.location='https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=byronic106@yahoo.com&lc=US&item_name=Donation+to +Help+Keep+Etymonline+Free+and+Open&no_note=0&cn=&curency_code=USD&bn=PP-DonationsBF:btn_donateCC_LG.gif:NonHosted'){kind=link}