(~s)
1.
A ~ is a formal written agreement between two or more people or groups of people which is recognized in law.
...the International Covenant on Civil and Political Rights.
N-COUNT
2.
A ~ is a formal written promise to pay a sum of money each year for a fixed period, especially to a charity. (mainly BRIT; in AM, usually use pledge )
If you make regular gifts through a ~ we can reclaim the income tax which you have already paid on this money.
N-COUNT: also by N