naphthide

from The Collaborative International Dictionary of English v.0.48

Naphthide \Naph"thide\ (n[a^]f"th[i^]d or n[a^]f"th[imac]d), n.
   (Chem.)
   A compound of naphthalene or its radical with a metallic
   element; as, mercuric naphthide.
   [1913 Webster]