What is Dation?

Legal Definition
Civil law, contracts. The act of giving something. It differs from donation, which is a gift; dation, on the contrary, is giving something without any liberality; as, the giving of an office.

2. Dation in payment, datio in solutionem, which was the giving one thing in payment of another which was due, corresponds nearly to the accord and satisfaction of the common law.
-- Bouviers Law Dictionary
Legal Definition
In the civil law. A gift; a giving of something. It is not exactly synonymous with "donation." for the latter implies generosity or liberality in making a gift, while dation may mean the giving of something to which the recipient is already entitled. See Dation en paiement.
-- Black's Law Dictionary
Legal Definition
An appointment, as to an office; a giving in fulfillment of a duty.
-- Ballentine's Law Dictionary