Definitions for "Bell jar"
A glass vessel, varying in size, open at the bottom and closed at the top like a bell, and having a knob or handle at the top for lifting it. It is used for a great variety of purposes; as, with the air pump, and for holding gases, also for keeping the dust from articles exposed to view.
a bell-shaped glass cover used to protect and display delicate objects or to cover scientific apparatus or to contain gases
a bell-shaped glass container
a piece of laboratory equipment designed to be hermetically sealed to a base-plate, and usually capable of being evacuated of air
A bell jar is a piece of laboratory glassware in the shape of a bell.