1590s, short for groom of the equirrie, from esquiry "stables" (1550s), from Middle French escuerie (Modern French écurie), perhaps from Medieval Latin scuria "stable," from Old High German scura "barn;" or from Old French escuier "groom," from Vulgar Latin scutarius "shield-bearer." In either case, spelling influenced by Latin equus "horse," which is unrelated.