equerry: [16] Nowadays in Britain simply royal attendants, equerries’ long and traditional association with the royal stables has led to association of the word equerry with Latin equus ‘horse’, but in fact the two are quite unrelated. Equerry originally meant ‘stable’, and was borrowed from the obsolete French escuirie (now écurie). It is not clear where this came from: some etymologists have linked it with Old High German scūr ‘barn, shed’, while others have derived it from Old French escuier ‘groom’ (source of English esquire and squire), according to which view it would mean ‘place where a groom stayed or worked’. (Escuier itself came ultimately from Latin scūtārius ‘shieldbearer’.) Forms such as escurie remained current in English up until the 18th century, but already by the 17th century equus-influenced spellings had begun to appear.
The person in charge of such a stable was formerly termed in French escuier d’escuirie ‘squire of the stable’, and in English groom of the equerry, and there are records from quite early in the 16th century indicating that equerry was being used on its own as the term for such a groom. => esquire, squire
equerry (n.)
royal officer, especially one charged with care of horses, 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" (German Scheuer); or else from Old French escuier "groom," from Vulgar Latin scutarius "shield-bearer." In either case, the spelling was influenced by Latin equus "horse," which is unrelated.
