(noun) a ceremonial feast of the American Indians of the northwest coast marked by the host's lavish distribution of gifts or sometimes destruction of property to demonstrate wealth and generosity with the expectation of eventual reciprocation / (noun) a social event or celebration / (verb) to give (as a gift) especially with the expectation of a gift in return / (verb) to hold or give a potlatch for (as a tribe or group) / (verb) to hold or give a potlatch
To assemble a full definition of debt, one would need to address philosophies of morality and justice and anthropologies of sacrifice and potlatch