- euthanasia (n.)
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- 1640s, "a gentle and easy death," from Greek euthanasia "an easy or happy death," from eu- "good" (see eu-) + thanatos "death" (see thanatology) + abstract noun ending -ia. Slightly earlier in Englished form euthanasy (1630s). Sense of "legally sanctioned mercy killing" is recorded in English by 1869.