(E)-2-(4-Diethyl-amino-2-hydroxy-benzyl-idene-amino)benzonitrile.

The mol­ecule of the title compound, C18H19N3O, displays a trans configuration with respect to the C=N double bond. The dihedral angle between the planes of the two benzene rings is 2.62 (11)°. A strong intra­molecular O—H⋯N hydrogen bond stabilizes the mol­ecular conformation.