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The term Canister originaly refered to a basket of woven reeds but is now commonly used to refer to any container that is roughly cylindrical in shape.
Canister is still widely used as a term for 35mm film containers, pods used for parachute supply drops and gas containers used for riot control.
A Canister is also a cylindrical shaped bell worn by sheep, that was traditionally used in Sussex England, especially on the South Downs.