(~s)
1.
A ~ is an object with flat circular ends and long straight sides.
...a ~ of foam...
It was recorded on a wax ~.
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2.
A gas ~ is a ~-shaped container in which gas is kept under pressure.
...oxygen ~s.
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3.
In an engine, a ~ is a ~-shaped part in which a piston moves backwards and forwards.
...a 2.5 litre, four-~ engine.
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