reciprocal altruism
A technical term in evolutionary biology and behavioral ecology, referring to altruistic behavior that is reciprocated over time.
Reciprocal altruism is one of the theories that explain cooperative behavior in organisms.
利他主義 is general altruism, while 互恵的利他主義 specifically refers to altruism that is reciprocated.
A compound of 互恵的 (reciprocal) + 利他主義 (altruism), likely a calque from English 'reciprocal altruism'.