What does euthanize mean?
Euthanize is a verb meaning to bring about a painless death, most commonly used of animals suffering from incurable illness, injury, or old age. A veterinarian might, for example, euthanize a dog whose cancer has become untreatable, sparing it further pain. The word derives from Greek: eu-, meaning 'good' or 'well', combined with thanatos, meaning 'death', so at its root it describes a 'good death'. While the noun euthanasia has existed in English since the seventeenth century, the verb euthanize emerged much later, in the early twentieth century. In everyday speech, especially in Britain, people more often say a pet was 'put down' or 'put to sleep', making euthanize sound somewhat clinical or formal. When applied to human beings, the term enters ethically charged territory surrounding assisted dying and physician aid-in-dying laws, which differ widely across jurisdictions. Because of this gravity, writers should use euthanize deliberately and precisely, recognizing both its compassionate intent and the sensitivity it carries.
verbTo put an animal to death painlessly, typically because it is suffering from an incurable or painful condition; by extension, sometimes used of a human being under legally sanctioned assisted dying.
- To kill (usually an animal) painlessly to end suffering from incurable illness or injury.
- To perform legally sanctioned assisted dying on a consenting terminally ill person.
"The veterinarian gently euthanized the elderly dog after its cancer became untreatable."
"Shelters that cannot find homes for animals may be forced to euthanize them."
"Several countries have enacted laws permitting doctors to euthanize patients who request it under strict safeguards."
The word literally means 'good death' — from Greek eu- (good) and thanatos (death) — making it one of the few words whose etymology openly states its own moral justification.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of euthanize
Euthanize comes from the Greek-derived noun euthanasia, formed from eu- ('good, well') plus thanatos ('death'), first recorded in English in the early 17th century as a term for a peaceful, painless death. The verb euthanize is a much later formation, attested from the early 20th century in American English, created by adding the verb-forming suffix -ize to the stem. Its sibling cognates include thanatology, the study of death, which shares the same Greek root thanatos.
Related word forms
How euthanize is actually used
Euthanize is standard and neutral in American usage; British English more often prefers 'put down' for pets. The verb is overwhelmingly used with animals; applying it to humans is sensitive and usually appears in formal medical or legal contexts discussing assisted dying.
Easily confused with euthanize
Euthanasia refers to ending life painlessly out of mercy for the individual, whereas eugenics is the attempt to improve a population's genetic quality through selective breeding — historically conflated in ways that carry very different moral meanings.