Merriam-Webster's Collegiate® Dictionary, 11th Edition
GROOM
I. noun
Etymology: Middle English grom
Date: 14th century
man , fellow ,
2. a. manservant , one of several officers of the English royal household, a person responsible for the feeding, exercising, and stabling of horses, bridegroom ,
II. verb
Date: 1809
transitive verb to clean and maintain the appearance of (as the coat of a horse or dog), to make neat or attractive , to get into readiness for a specific objective ; prepare , intransitive verb to groom oneself