Shaker (emphasis on the first "e") is a vessel in the form of a large glass with a lid, designed to shake cocktails.
The English word "shake" is pronounced "shake" and means "shake, shake". In modern shakers, there is a special mechanism for pouring ingredients and filling the resulting mixture.
By the way, the shaker is not just about bartenders. To mix white paint with color dyes, huge mechanisms of shaking cans are used, which are also called shakers.
Shaker is on the list: Cooking