equerry
/ˈekwərɪ/noun
(pl. -ies)
1- an officer of the British royal household who attends or assists members of the royal family英国王室侍从武官。
1.1
- historical an officer of the household of a prince or noble who had charge over the stables〈史〉（王室、贵族的）掌马官。
词源
early 16th cent. （formerly also as esquiry ）： from Old French esquierie 'company of squires, prince's stables', from Old French esquier 'esquire', perhaps associated with Latin equus 'horse'. The historical sense is apparently based on Old French esquier d'esquierie 'squire of stables'.