From Law wiki, the wiki for law research

1. A payment to discharge a debt.

2. A Trust in which there are Successive interests, that is, where the trust benefits one person or group of people for a particular length of time, then another. A common form of settlement is to create a trust such that the benefit of an estate is conferred on one person for life (a Life interest), with the absolute estate passing to someone else on the death of the person with the life interest. For example, a man may stipulate in his Will that his interest in the family home be held on trust for his wife for the rest of here life, and then divided equally amoing their children. A person who makes a settlement is referred to as a Settlor but, confusingly, the term 'settlor' is also used of anyone who creates an Express trust, not just a settlement.

3. A vague term used in trust law to mean a fund of money or property. Under this definition, almost any trust can be said to be a settlement.