The Collaborative International Dictionary of English v.0.48:

Sphingid \Sphin"gid\, n. (Zool.)
   A sphinx.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sphingid \Sphin"gid\, a.
   Of or pertaining to a sphinx, or the family Sphingidae.
   [1913 Webster]

WordNet (r) 3.0 (2006):

sphingid
    n 1: any of various moths with long narrow forewings capable of
         powerful flight and hovering over flowers to feed [syn:
         hawkmoth, hawk moth, sphingid, sphinx moth,
         hummingbird moth]