Definition of altruist
- Kim signed up with Compass, a District-based group that serves the growing number of altruists who donate not only time and money to charity and the arts but also their professional expertise.
- —Robert McCartney
- Reciprocal altruism refers to the exchange of beneficial acts between individuals, in which the benefits to the recipient exceed the cost to the altruist. … Although the potential for reciprocal altruism exists in many animal societies, most interactions occur between closely related individuals …
- —Robert M. Seyfarth et al.