سَيْحٌ
1.
Running water; (S, Msb;) a verbal noun used as a subst.: (Msb:) or running external water: (K:) or external water running upon the surface of the earth: (T, TA:) the water of rivers and valleys: (Mgh:) plural سُيُوحٌ. (T, TA.) [And it is used as an epithet:] you say also (TA) مَاءٌ سَيْحٌ (A, TA) and
سَايءِحٌ (A) Water running upon the surface of the earth: (A, TA:) plural of the former أَسْيَاحٌ. (TA.)