If you are thinking about a 'wine professional' then a Sommelier
Cork
Cork
Plug
cork is a stopper to close wine bottles
A beaker cover is called a rubber stopper or metal stopper(depends on what the stopper is made of).
Bottle stoppers can generally be purchased at a range of stores. These include supermarkets, corner shops, and the slightly higher-end of wine stores and off licenses.
Decanter or carafe
Decanter
The purpose of a wine stopper is to cork the remaining wine in a bottle before putting it on a rake or into the refrigerator since using the original cork is sometimes difficult to put back into the bottle.
A CORK stopper is a plug for a bottle made of cork
Grease the top of the bottle!
It is called ullage
the " punt ".