Definition of altruistic
: relating to or given to altruism:
a : having or showing an unselfish concern for the welfare of others
altruistic acts/motives a generous and altruistic person Yet many of the most important institutions in our society—the fine arts, NGOs, humanitarian charities—depend on the generosity of wealthy citizens with altruistic impulses.— Jonathan Kay
b : relating to or being behavior by an animal that is not beneficial to or may be harmful to the animal itself but that benefits others of its species
The evolutionary theory of kin selection requires that social animals recognize their relatives so that altruistic behavior can be displayed preferentially toward kin. — Science
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Time Traveler for altruistic
The first known use of altruistic was in 1853
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