The title compound, C30H18ClNO, is a product of the condensation reaction of acenaphthyl-ene-1,2-dione and 5'-chloro-1,1':3',1''-terphenyl-4'-amine. The acenaphthyl-ene fragment and two terminal phenyl rings are rotated relative to the central benzene ring by 72.2 (3), 43.2 (3) and 41.2 (3)°, respectively. This mol-ecular conformation is supported by weak C-H⋯π inter-actions. In the crystal, mol-ecules form centrosymmetric dimers by the stacking inter-actions between two neighboring acenaphthyl-ene fragments, with an inter-planar distance of 3.365 (3) Å. The dimers are bound to each other by weak C-H⋯N and C-H⋯π inter-actions, forming a three-dimensional framework.