Source : Webster's Revised Unabridged Dictionary (1913)

Clough \Clough\, n. [OE. clough, cloghe, clou, clewch, AS.
   (assumed) cl[=o]h, akin to G. klinge ravine.]
   1. A cleft in a hill; a ravine; a narrow valley. --Nares.

   2. A sluice used in returning water to a channel after
      depositing its sediment on the flooded land. --Knight.

Clough \Clough\ (?; 115), n. (Com.)
   An allowance in weighing. See {Cloff}.