Altruistic

/ˌæltruˈɪstɪk/ adjective easy

Showing a genuine concern for the well-being of others, often at some cost to oneself.

The volunteer's altruistic decision to donate a kidney to a stranger amazed her coworkers.

Memory Trick

Altruistic contains 'altru,' close to the Latin root for 'other' — altruistic people put others first, not themselves.