an officer of a royal or similar household, charged with the care of the horses.
2.
an officer of the British royal household who attends the sovereign or other member of the royal family.
Origin: 1520–30; alteration (influenced by Latin equus horse) of earlier esquiry, escuirie < Middle French escuirie stable, squires collectively, derivative of escuyersquire; see -y3
1591, short for groom of the equirrie, from esquiry "stables," from M.Fr. escuerie, perhaps from M.L. scuria "stable," from O.H.G. scura "barn;" or from O.Fr. escuier "groom," from V.L. scutarius "shield-bearer." In either case, spelling infl. by L. equus "horse," to which it is not related.