The member of staff at a restaurant who keeps the wine cellar and advises the guests on a choice of wines; a wine steward / stewardess, a wine waiter / waitress / server.
verb
To act as a sommelier.
valet-de-chambre
noun
A valet.
The personal servant of a monarch.
How often have the words sommelier and valet-de-chambre occurred in a corpus of books? (source: Google Ngram Viewer )