The Collaborative International Dictionary of English v.0.48:

Anicut \An"i*cut\, Annicut \An"ni*cut\, n. [Tamil anai kattu dam
   building.]
   A dam or mole made in the course of a stream for the purpose
   of regulating the flow of a system of irrigation. [India]
   --Brande & C.
   [1913 Webster]