A shaker is a device used in chemistry and biology laboratories to stir liquids.
A typical shaker has a table board that oscillates horizontally, powered by an electric motor. The liquids to be stirred are held in beakers, jars, or Erlenmeyer flasks that are placed over the table; or, sometimes, in test tubes or vials that are nested into holes in the plate.
Shakers have been replaced by magnetic stirrers for many purposes, but are still favored for some situations.