is the old Dutch gom (a young man). Thus, Groom of the Stole is the young man over the wardrobe. Groom, an ostler, is quite another word, being the Persian garma (a keeper of horses), unless, indeed, it is a contracted form of stable-groom (stable-boy). The Anglo Saxon Bryd-guma (guma = man) confused with groom, a lad.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894