(1) In Theravada, the mental factor of wishing to give material things to all beings, so that they may be happy, without investigating whether or not they are worthy to receive them. (2) In Mahayana, the mental urge that leads one to wish to give to others all that is one's own – one's body, material wealth, and the roots of one's constructive actions. When conjoined with a bodhichitta aim, it becomes a far-reaching attitude.
Tibetan: སྦྱིན་པ། sbyin-pa
J. Hopkins: Donation; verb: give; bestow; present noun: giving; gift; present; alms.