A wine steward is part of a restaurant establishments staff. They will execute duties that require the knowledge level of a Sommelier. They will suggest wines based off of that knowledge, present, open, decanter and serve the wines within a restaurant.
A Sommelier is not only able to execute those duties but has become an expert in the area of wine in general and does not necessarily require that person to be in the employment of a restaurant. There are some Sommelier's that have used their knowledge in the area of wine solely to write about wines rather then serve it.
You can equate the difference similar to being a Professor in a certain field of education and being educated in that same field. One uses it as a profession the other maintains the education level.
wine steward, wine sommelier.
She is called a Wine Steward or a Sommelier.
Wine Steward
The word is Sommelier, a wine steward.
Sommelier, or Wine Steward, or oenologist.
One of the duties of a Food and Beverage Steward is to provide hospitality services to guests. Responsibilities of the Food and Beverage Steward include handling special requests made by the guests and overseeing other staff members.
There is no dictionary entry for the word, "semmiler." Perhaps the closest would be sommelier (a wine steward), similar, or Semmler (a sir name).
Officially there just called wine testers, they don't any special name.
A sommelier.
Sommelier
In England we call these folks Wine Waiters. Someone who is trained in the serving of wine is a 'sommelier'.
A sommelier is an expert in the art of serving wine. High end restaurants, wine bars, clubs etc hire a certified sommelier to over see many aspects. Their responsibilities include pairing wine with food, making sure the wine is rotated and stored properly, training the staff on serving wine. They may also be in charge of ordering and putting together the wine list.