A more thorough explanation:

datio (day-shee-oh), n. [from Latin dare “to give”] is a term used in Roman law.

1. An act of giving, as in datio in solutum (“giving in payment”).
2. An appointment, as in datio tutoris (“appointment of a guardian”).

The plural form of datio is dationes (day-shee-oh-neez).

Example:

If someone owes money to another person, they can offer something else as payment instead of money. This is called datio in solutum. For example, if someone owes $100 but doesn't have the money, they can offer a watch worth $100 instead.

Explanation:

The example illustrates the first definition of datio, which refers to an act of giving. In this case, the debtor is giving something else (the watch) instead of the money they owe.

Example:

When a child's parents die, a guardian needs to be appointed to take care of them. This is called datio tutoris. For example, if a child's parents die and they have no other family members to take care of them, a court can appoint a guardian to be responsible for the child.

Explanation:

The example illustrates the second definition of datio, which refers to an appointment. In this case, a guardian is appointed to take care of the child.