/'kænɪstə(r); `kænɪstɚ/
n
1 small (usu metal) container for holding tea, coffee, etc （通常为金属的）小罐（装茶叶、咖啡等）.
2 cylinder, filled with shot or tear-gas, that bursts and releases its contents when fired from a gun or thrown 霰弹筒（内装弹丸或催泪气体, 以枪炮发射或投掷後爆炸）.

n[C]
[Date: 1400-1500; Language: Latin;Origin: canistrum 'basket', from Greek kanastron, from kanna; CANE¹]
a round metal case that contains gas and bursts when it is thrown or fired from a gun
　Police fired tear gas canisters into the crowd.
a metal container for keeping something in
　a tea canister
　a petrol canister