1. statute of limitations; lapse of rights after a period of time; prescription (including acquisitive and extinctive prescription)
2. becoming invalid or void after a set time
3. ageing; agingChemistry term, See also 時効硬化
Wikipedia definition
4. Statute of limitationsA statute of limitations is an enactment in a common law legal system that sets the maximum time after an event that legal proceedings based on that event may be initiated. In civil law systems, similar provisions are typically part of the civil code or criminal code and are often known collectively as periods of prescription.
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