mercy kill vs euthanize

mercy kill and euthanize both are verbs.

Word	Noun	Adjective	Verb	Adverb
mercy kill	No	No	Yes	No
euthanize	No	No	Yes	No

As verbs, mercy kill and euthanize are synonyms defined as:

mercy kill and euthanize: intentionally cause the painless death of a person or animal

Other synonyms of mercy kill include euthanatise, euthanatize, euthanise.

mercy kill (verb)	euthanize (verb)
intentionally cause the painless death of a person or animal	intentionally cause the painless death of a person or animal