imprescriptible
/ˌɪmprɪsˈkrɪptəbl/adjective
- Law (of rights) unable to be taken away by prescription or by lapse of time【律】（权利）不受法律约束的, 不受时效限制的。
词源
late 16th cent.: from medieval Latin imprescriptibilis, from in- 'not' + Latin praescript- （from praescribere 'prescribe'）.