A canister is a small container with a lid, often made of metal. You might keep a canister of sugar in your kitchen next to a canister of tea.

Typically, a canister is round and has a fitted lid — while kitchen canisters are usually metal, the canisters that hold a roll of camera film are made of plastic. Another type of canister is a cylinder that's packed with shot or filled with pressurized gas and shot out of a weapon. In the 15th century, the word meant "basket," from the Latin canistrum, "wicker basket," with its Greek root kanystron, "basket made of reeds." The meaning of canister probably changed to "metal container" because of the word can.

Definitions of canister
  1. noun
    a round container (often made of metal) for storing dry foods such as tea or flour
    synonyms: cannister, tin
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    type of:
    any object that can be used to hold things (especially a large metal boxlike object of standardized dimensions that can be loaded from one form of transport to another)
  2. noun
    a metallic cylinder packed with shot and used as ammunition in a firearm
    synonyms: canister shot, case shot
    see moresee less
    type of:
    ammo, ammunition
    projectiles to be fired from a gun
Word Family

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