What is Rung Bell?
1.
When you do something that you can't take back or reverse(i.e. as in you can't un-ring that bell).
Jan's decision to have a one night stand is a rung bell.
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2.
When something makes someone so mad, he has a rung bell and is going to fight no matter what.
Look-out, whatever you said now he has a rung bell.
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