The term "mercy killer" refers to someone who kills another person out of compassion or to alleviate their suffering. However, there are several other synonyms for this term, some of which include "euthanizer," "angel of death," "end-of-life caregiver," "palliative caretaker," and "compassionate killer." While the act of mercy killing is often controversial and illegal in many jurisdictions, there are situations where individuals may feel compelled to end the life of a loved one or someone else who is suffering from a terminal illness or injury. Regardless of the terminology used, the decision to end a life should always be taken seriously, and professional medical advice and support should be sought whenever possible.