Altruism
The Oxford dictionary:
The belief in or practice of disinterested and selfless concern for the well-being of others.
Selfless behavior and altruism are closely related concepts, but they have subtle and albeit stark contrasting differences in their definitions and implications.
Altruism is “behavior of an animal that benefits another at its own expense.”
the concern for the well-being of others, independently of personal benefit or reciprocity.