Euthanasia refers to an act or practice of causing death painlessly in order to end suffering: advocated by some as a way to deal with persons dying of incurable, painful diseases.
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Euthanasia is defined as a killing of another person or practice of ending someone's life as an act of mercy or for the purpose of terminating the individual's suffering. It refers to termination of life by the injection of a lethal drug. Euthanasia which means "good death" is the practice of allowing people who have a terminal illness to die. The word is mainly used now to refer to situations in which one individual contributes to the death of another person in order to end the suffering of that second person