The Collaborative International Dictionary
Dinaphthyl
Dinaphthyl \Di*naph"thyl\, n. [Pref. di- + naphthylene.] (Chem.) A colorless, crystalline hydrocarbon, C20H14, obtained from naphthylene, and consisting of a doubled naphthylene radical.
Wiktionary
dinaphthyl
n. 1 (context organic chemistry especially in combination English) Two naphthyl radicals in a compound 2 (context organic compound English) binaphthyl