Webster's Revised Unabridged Dictionary · 1913

Groom

Groom , noun

[Compare Scot. grome, groyme, grume, gome, guym, man, lover, OD. grom boy, youth; perh. the r is an insertion as in English bridegroom, and the word is the same as Anglo-Saxon guma man. See Bridegroom.]

1.
A boy or young man; a waiter; a servant; especially, a man or boy who has charge of horses, or the stable. — Spenser
2.
One of several officers of the English royal household, chiefly in the lord chamberlain's department; as, the groom of the chamber; the groom of the stole.
3.
A man recently married, or about to be married; a bridegroom. — Dryden
Collocations (1)
Groom porter , formerly an officer in the English royal household, who attended to the furnishing of the king's lodgings and had certain privileges.

Groom , intransitive verb

To tend or care for, or to curry or clean, as a, horse.