Law. An artificial water channel or (later also) natural stream, brook, etc., which a person is entitled to make use of, esp. one that flows…

Scots Law. A servitude (servitude, n. 3a) giving the owner of a property the right to use water from another property, esp. for the purpose of…

the right to the use of water in a tract of land (cf. water privilege n. (a)), or to navigate on particular waters; also in singular in same sense.

(a) the right to use water (formerly esp. the right to use running water to drive machinery); frequently in plural; †(b) a stream or body of water…

U.S. A (section of) river capable of powering machinery, as for a mill, factory, etc.; = water privilege n. (b) at water, n. compounds 7. Obsolete.