3-[(E)-(7-Chloro-4-quinol-yl)hydrazono-meth-yl]benzonitrile monohydrate.

The title monohydrate, C17H11ClN4·H2O, features an essentially planar organic mol­ecule, as seen in the dihedral angle of 2.42 (8)° formed between the quinoline and benzene planes. The conformation about the imine bond is E, and the N—H group is oriented towards the quinoline residue. The major feature of the crystal packing is the formation of supra­molecular chains along [100], whereby the water mol­ecule accepts one N—H⋯O hydrogen bond and makes two O—H⋯N hydrogen bonds. A C—H⋯O link is also present.