euthanasia
noun [ U ] uk/ˌjuː.θəˈneɪ.zi.ə/ us/ˌjuː.θəˈneɪ.ʒə/
安乐死
the act of killing someone who is very ill or very old so that they do not suffer any more
Although some people campaign for the right to euthanasia, it is still illegal in most countries. 尽管一些人发起运动争取安乐死的权利，但在大多数国家中实施安乐死仍是违法行为。
Synonym: mercy killing